Journal articles: 'TI02 COMPOSITE'

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Shi, Dan, Zhi Li Zhang, De Cai Li, Qi Han, and Tie Peng Xing. "Preparation and Photo-Catalysis Properties of Fe₃O₄/TiO₂ Nanocomposite." Key Engineering Materials 512-515 (June 2012): 187–90. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.187.

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As a Kind of Most Common Used Photocatalyst, TiO2 Nanomaterials Existing Disadvantages on Low Light Energy Utilization in Visible Light Range and Difficulty on Recycle. in Our Study, Different Proportions of Fe3+ and Fe2+ Ion Were Doped with Nano-Ti02 Particles in Structure of Rutile Type through Method of Chemical Precipitation. the Result Showed that Nano-Composites Formed by TiO2 Coexist with Fe3O4, with the Average Size of the Composite Particles Nearly 20 Nm. the Photo-Catalyst Performances of the Composite Have Improved Largely, and so the Relatively Optimized Preparation Conditions Were Presented.

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Hui, Yang, Zhang Jiaqi, and He Huan. "Preparation of carbon nanotubes/TiO₂-polyvinylidene fluoride nanocomposites and composite films." Journal of Physics: Conference Series 2263, no. 1 (April 1, 2022): 012001. http://dx.doi.org/10.1088/1742-6596/2263/1/012001.

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Abstract In this paper, PVDF membrane was discussed, many modified materials were found from the shortage of materials, and finally carbon nanotubes/TiO2 hybrid materials were synthesized. The preparation methods and synthesis conditions of carbon nanotubes/TiO2-polyvinylidene fluoride nano composite ultrafiltration membrane were studied, and the advanced membrane treatment technology was prospected. Secondly, multi-walled carbon nanotubes/Ti02 hybrid materials were synthesized by hydrothermal method and sol-gel method.

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Svec, Pavol, and L’ubomír Caplovic. "Microstructure and mechanical properties of b4c-tib2 composites reactive sintered from B4C + TiO2 precursors." Processing and Application of Ceramics 16, no. 4 (2022): 358–66. http://dx.doi.org/10.2298/pac2204358s.

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Ceramic composites consisting of a boron carbide (B4C) matrix and titanium diboride (TiB2) secondary phase were obtained by reactive sintering from boron carbide powder with 40 and 50wt.% of titanium dioxide (TiO2) additive. The same sintering temperature of 1850?C and pressure of 35MPa, but different sintering times from 15 to 60min, were applied during reactive hot pressing of the composites in vacuum. The effects of TiO2 content and sintering time on phase compositions, microstructures and mechanical properties of the composites were studied. The TiO2 additive enhanced densification of the B4C-TiB2 ceramic composites. Both Vickers hardness and the fracture toughness of the composites increased with prolongation of sintering time. The highest hardness of 29.8GPa was achieved for the composite with 29.6 vol.% of TiB2 obtained by sintering of the precursor with 40wt.% of TiO2 additive for 60min. The fracture toughness reached a maximum value of 7.5MPa?m1/2 for the composite containing 40.2 vol.% of TiB2, which was fabricated by reactive sintering of the precursor with 50wt.% of TiO2 additive for 60min.

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Wang, Gui Song, and Lin Geng. "Microstructure Formation Mechanism of (Al₂O₃+TiB₂+Al₃Ti)/Al Composites Fabricated by Reactive Hot Pressing." Key Engineering Materials 353-358 (September 2007): 1439–42. http://dx.doi.org/10.4028/www.scientific.net/kem.353-358.1439.

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The two (Al2O3+TiB2+Al3Ti)/Al composites were fabricated from Al-B2O3-TiO2 and Al-B-TiO2 raw powders by reactive hot pressing, respectively. The microstructure of in situ two composites was analyzed by OM, SEM and TEM. The results showed that coarse Al3Ti blocks with several tens of micrometers size were formed during hot pressing. The equiaxed Al2O3 particulates and hexagonal TiB2 particulates with finer sizes were formed in the composites simultaneously. The microstructure formation mechanism of (Al2O3+TiB2+Al3Ti)/Al composites were discussed. The results showed that Al2O3 reinforcements were formed on the surface of TiO2 or B2O3 powder and TiB2 particles were formed on B or B2O3 powders. The formation of coarse Al3Ti block is result from continuous diffusion of Ti in liquid Al during reactive hot pressing. In addition, there are fine Al3Ti precipitates exist in the composite fabricated from Al-B-TiO2 powders. This contributes to the improved mechanical properties in terms of yield and ultimate stresses and Young’s modulus of the composite.

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Kustiningsih, Indar, Fajariswaan Nurrahman, Hasby Ashyra Rinaldi, Ipah Ema Jumiati, Denni Kartika Sari, and Jayanudin Jayanudin. "Synthesize Fe3O4-TiO2 Composite for Methyl Orange Photocatalytic Degradation." Materials Science Forum 1057 (March 31, 2022): 129–35. http://dx.doi.org/10.4028/p-9q4ts9.

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The effect of Fe3O4 percentage on Fe3O4-TiO2 composite for methyl orange photocatalytic degradation has been investigated. Hydrothermal was carried out on TiO2 before being combined with Fe3O4 by precipitation method. The composites were characterized by means of Scanning Electron Microscope (SEM), X-ray diffraction (XRD) and UV-Vis diffuse and reflectance spectroscopy (UV-Vis DRS). The photocatalytic activity of Fe3O4-TiO2 composites were evaluated for methyl orange degradation. The addition of Fe3O4 to TiO2 could reduce the bandgap energy. The lowest bandgap energy was obtained at 20% Fe3O4-TiO2 composite. By using this composited, the degradation of methyl orange was 90%.

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Noviyanti, Atiek Rostika, Efa Nur Asyiah, Muhamad Diki Permana, Dina Dwiyanti, Suryana, and Diana Rakhmawaty Eddy. "Preparation of Hydroxyapatite-Titanium Dioxide Composite from Eggshell by Hydrothermal Method: Characterization and Antibacterial Activity." Crystals 12, no. 11 (November 10, 2022): 1599. http://dx.doi.org/10.3390/cryst12111599.

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Hydroxyapatite (HA) has been widely used in biomedical applications. HA is prepared from natural sources of eggshell. The obtained HA is composited with TiO2 using the hydrothermal method at a temperature of 230 °C. The structure and morphology of HA-TiO2 composites are characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and a scanning electron microscope (SEM). Meanwhile, its antibacterial activity was tested on Staphylococcus aureus and Escherichia coli bacteria. The formation of the HA-TiO2 composite is evidenced by typical peaks on the XRD pattern for HA and TiO2. The FTIR spectrum shows that no bond formed between TiO2 and HA which indicates the formation of composites. The smallest crystallite size and the highest specific surface area were obtained from the composite with the composition of HA-TiO2 30:70. In addition, the composition of the composite also shows the smallest particle size distribution. Therefore, the presence of TiO2 plays a significant role in determining the HA properties formed. Furthermore, the HA-TiO2 composite showed good antibacterial activity using disk diffusion and optical density (OD) methods. These results indicate that the synergistic combination of HA from eggshell with TiO2 has favorable properties for antibacterial activity.

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Niyomwas, Sutham. "Synthesis of TiO₂-B₂O₃-Al Based Porous Composites." Advanced Materials Research 626 (December 2012): 1–5. http://dx.doi.org/10.4028/www.scientific.net/amr.626.1.

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The TiB2-Al2O3 porous composites were obtained in situ by self-propagating high temperature synthesis (SHS) of TiO2-B2O3-Al System. The reaction was carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the reacting species. The effects of increasing aluminum mole ratio to the precursor mixture of TiO2, B2O3 and Al were investigated. XRD and SEM analyses indicate complete reaction of precursors to yield TiB2-Al2O3 as product composite

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Yeh, Chun-Liang, and Fu-You Zheng. "Formation of TiB2–MgAl2O4 Composites by SHS Metallurgy." Materials 16, no. 4 (February 15, 2023): 1615. http://dx.doi.org/10.3390/ma16041615.

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TiB2–MgAl2O4 composites were fabricated by combustion synthesis involving metallothermic reduction reactions. Thermite reagents contained Al and Mg as dual reductants and TiO2 or B2O3 as the oxidant. The reactant mixtures also comprised elemental Ti and boron, as well as a small amount of Al2O3 or MgO to serve as the combustion moderator. Four reaction systems were conducted and all of them were exothermic enough to proceed in the mode of self-propagating high-temperature synthesis (SHS). The reaction based on B2O3/Al/Mg thermite and diluted with MgO was the most exothermic, while that containing TiO2/Al/Mg thermite and Al2O3 as the diluent was the least. Depending on different thermites and diluents, the combustion front temperatures in a range from 1320 to 1720 °C, and combustion wave velocity from 3.9 to 5.7 mm/s were measured. The XRD spectra confirmed in situ formation of TiB2 and MgAl2O4. It is believed that MgAl2O4 was synthesized through a combination reaction between Al2O3 and MgO, both of which can be totally or partially produced from the metallothermic reduction of B2O3 or TiO2. The microstructure of the TiB2–MgAl2O4 composite exhibited fine TiB2 crystals surrounded by large densified MgAl2O4 grains. This study demonstrated an energy-saving and efficient route for fabricating MgAl2O4-containing composites.

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da Rocha, Rosa Maria, and Francisco Cristóvão Lourenço de Melo. "Effect of TiO₂ and TiB₂ on Pressureless Sintering of B₄C." Materials Science Forum 727-728 (August 2012): 1022–27. http://dx.doi.org/10.4028/www.scientific.net/msf.727-728.1022.

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This paper presents results of experiments on pressureless sintering of boron carbide (B4C) with addition of titânia (TiO2) and titanium diboride (TiB2). The TiB2powder was added as a second phase and the TiO2powder for reactive sintering and in-situ formation of TiB2. The final concentrations of TiB2in the composites were 0 to 10 vol%. Sintering was performed at 2050 °C/30min in argon atmosphere. TiO2was completely transformed into TiB2with fine equiaxed grains distributed homogeneously. Composites obtained by in-situ reaction showed a densification increase with the concentration increase, while the composites with TiB2powder mixture showed low densification in all compositions. Relative Density of the composite with 10 vol% of TiB2obtained in-situ was 91% (TD) compared to 86 % for B4C only. Vickers hardness was about 29 GPa.

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Li, Shaolin, Xiuhua Guo, Shengli Zhang, Jiang Feng, Kexing Song, and Shuhua Liang. "Arc erosion behavior of TiB2/Cu composites with single-scale and dual-scale TiB2 particles." Nanotechnology Reviews 8, no. 1 (December 31, 2019): 619–27. http://dx.doi.org/10.1515/ntrev-2019-0054.

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AbstractArc erosion behaviors of TiB2/Cu composites with single-scale and dual-scale TiB2 particles fabricated by powder metallurgy were studied. It was revealed that the dual-scale TiB2/Cu composites had fewer structure defects compared with the single-scale TiB2/Cu composites, and TiB2 particles with different size were uniformly distributed in the copper matrix. When the ratio of 2 μm over 50 μm TiB2 particles is 1:2, the density of TiB2/Cu composite is 98.5% and shows best mechanical and thermal properties. The arc duration and energy of TiB2/Cu composites increase with the increase of electric current in contact material testing. Compared with the single-scale TiB2/Cu composites, the arc erosion of dual-scale TiB2/Cu composite with 2 μm+50 μm (1:2) TiB2 was slighter. The anode bulge area and cathode erosion pit of dual-scale TiB2/Cu composite was smaller. The dual-scale TiB2 particles optimize the microstructure and thermal stability of the composite, which is conducive to alleviating arc erosion. The synergistic effect of different sized TiB2 particles in the matrix improved the arc erosion resistance of TiB2/Cu composite during arcing.

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Yeh, Chun-Liang, and Kuan-Ting Liu. "Synthesis of TiB2/TiC/Al2O3 and ZrB2/ZrC/Al2O3 Composites by Low-Exotherm Thermitic Combustion with PTFE Activation." Journal of Composites Science 6, no. 4 (April 7, 2022): 111. http://dx.doi.org/10.3390/jcs6040111.

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TiB2–TiC–Al2O3 and ZrB2–ZrC–Al2O3 composites were produced via PTFE (polytetrafluoroethene)-activated combustion synthesis involving low-exotherm thermites. The reactant stoichiometries were 3TiO2 + 4Al + 0.5B4C + (1 − x)C + xCPTFE and 3ZrO2 + 4Al + 0.5B4C + (1 − y)C + yCPTFE. PTFE played a dual role in promoting the reaction and carburizing reduced Ti and Zr. The threshold amount of PTFE for the TiO2/Al-based reaction was 2 wt% (i.e., x = 0.15) and for the ZrO2/Al-based reaction was 3 wt% (i.e., y = 0.25). The increase in PTFE increased the combustion front velocity and reaction temperature. The TiO2/Al-based reaction was more exothermic than the ZrO2/Al-based reaction and exhibited a faster combustion front and a lower activation energy. The TiB2–TiC–Al2O3 composite was produced with the minimum amount of PTFE at x = 0.15. The formation of ZrB2–ZrC–Al2O3 composites required more PTFE at y = 0.5 to improve the reduction of ZrO2. Both triplex composites displayed mixed microstructures consisting of short-rod borides, fine spherical carbides, and Al2O3 agglomerates.

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Xu, Shao Fan, Shao Ping Xu, Cheng Nan Zhu, and Chuan Yong Yuan. "Preparation and Properties of Cf-TiB2-Cu-Graphite Composites." Advanced Materials Research 535-537 (June 2012): 8–13. http://dx.doi.org/10.4028/www.scientific.net/amr.535-537.8.

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Copper-plated TiB2-Cu-graphite composite, Cf-TiB2-Cu-graphite composite and Cf-copper-plated TiB2-Cu-graphite composite with the same TiB2 content were prepared by the powder metallurgy method. Physical and mechanical properties of these composites were tested. The dry friction tests of the composites under sliding velocity of 10m/s and load of 4.9N were conducted for 36h. The results show that the properties of the Cf-copper-plated TiB2-Cu-graphite composite such as electric conductivity, hardness, bending strength and wear resistance are increased remarkably than those of either Cf-TiB2-Cu-graphite or copper-plated TiB2-Cu-graphite composites.

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13

Bravo Barcenas, David Israel, Jorge Manuel Chávez Aguilar, Omar Jiménez Alemán, Luis Olmos Navarrete, Max Fernando Flores Jiménez, Marco Aurelio González Albarrán, and Iván Gerardo Farias Velázquez. "Microstructure and Mechanical Properties of Ti-TiH2 Based Matrix Composites Reinforced with xTiB2 Particles Processed by Powder Metallurgy." Coatings 13, no. 3 (March 9, 2023): 587. http://dx.doi.org/10.3390/coatings13030587.

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The structure changes, microstructure evolution, and mechanical properties during Powder Metallurgy (PM) through High Vacuum Sintering of a Ti-TiH2 matrix reinforced with Titanium Diboride (TiB2) particles were investigated. Composites were fabricated at 850, 1100, and 1300 °C. The strategy for the fabrication process was to use the PM route employing titanium hydride (TiH2) to reduce the consumption of Commercially Pure Titanium (CP-Ti). The structure of the composites was analyzed using X-Ray Diffraction (XRD), while Optical Microscopy (OM), and Field-Emission Scanning Electron Microscopy (FE-SEM) analysis were used to study the microstructure. Vickers microhardness and nanoindentation were performed to evaluate the elastoplastic and mechanical properties. According to the results, the unreinforced Ti-TiH2 sample presented higher sinter-ability, attaining relative density values of 93% with the higher sintering temperature. Composite samples showed TiB and TiB2 phases without the presence of any TiH2 residual phase. The highest mechanical properties were measured for reinforced samples with 30 vol.% of TiB2, sintered at 1300 °C, showing values of 509.29 HV and 4.94 GPa for microindentation Vickers and nanoindentation essays, respectively, which resulted in 8.5% higher than the values for the unreinforced sample. In addition, their H/Er and H3/Er2 ratios are higher than those of CP-Ti suggesting a better wear resistance of the Ti-TiH2 matrix-reinforced samples, combined with its mechanical properties makes it more suitable than CP-Ti for its potential in biomedical applications.

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Maganti, Naga Venkata Ramesh, and Ravikanth Raju Potturi. "Investigation on Mechanical and Machinability Properties of Aluminium Metal Matrix Composite Reinforced with Titanium Oxide (TiO2) and Graphite (Gr) Particles." Trends in Sciences 20, no. 11 (August 25, 2023): 5682. http://dx.doi.org/10.48048/tis.2023.5682.

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This research paper deals with the preparation process and testing of metal matrix composites comprising Aluminium alloy (Al 6061) as the base metal and Titanium oxide (TiO2) and Graphite (Gr) as reinforcements. Due to their high specific strength, superior malleability, lightweight, stiffness and excellent resistance to corrosion, oxidation and wear, the aluminium metal matrix composites are preferred in the automobile and industrial sectors for component manufacturing. No work reported on machinability properties of Titanium oxide (TiO2) and Graphite (Gr) reinforced aluminium composites so far. This study prepared and studied samples composed of variable proportions of titanium oxide and graphite. The samples were prepared using the stir casting method. While stirring, the required additives were added to the molten aluminium mixture. To perform the tests, the samples were prepared according to standard dimensions after solidification. The mechanical properties of the prepared composite were examined using various test procedures, such as strength and hardness. Scanning electron microscopy was used to examine the microstructure of the test composite samples. The EDAX test confirmed the presence of graphite and Titanium oxide in the aluminium based composite specimens. Furthermore, machining was done to study the cutting forces on the tool. The test results showed a significant impact of the reinforced materials on the mechanical and machinability properties of aluminium metal matrix composites. Gr decreases hardness, while TiO2 increases it. TiO2 and Gr reinforcements increase the tensile strength of Al 6061 composites. The addition of TiO2 decreased the composite's elongation. The proof strength of 2 % Al6061 was high, however it decreased with 3 % Gr and increased with TiO2 reinforcement. Reinforcements increase cutting forces during machining; when comparing the machining of Al 6061 to that of 3 % Gr and 5 % TiO2, a 50 % increase in cutting forces is noticed. However, excessive reinforcements may reduce cutting forces due to poor matrix-reinforcement adhesion. HIGHLIGHTS The mechanical and machinability properties of aluminium metal metrics reinforced with Titanium oxide (TiO2) and graphite (Gr) have not been reported so far in the literature. In this study, aluminium based composites reinforced with variable proportions of titanium oxide and graphite were prepared and studied. The fabrication process was done by stir casting by adding the required additives into the molten mixture of aluminium, followed by continuous stirring. The solidified samples were cut according to the standard dimensions and various test procedures were conducted to examine the mechanical and machinability properties of the prepared composites. Gr reduces hardness, whereas TiO2 enhances it. TiO2 and Gr reinforcements boost Al 6061 composite tensile strength. TiO2 addition reduced elongation of the composite. 2 % proof strength of Al 6061 was strong, however it dropped with 3 % Gr and rose with TiO2 reinforcement. Reinforcements results higher cutting forces while machining, however excessive supplements lower cutting forces may be due to poor matrix-reinforcement bonding. GRAPHICAL ABSTRACT

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Zhu, De Gui, Hong Liang Sun, Yu Shu Wang, and Liang Hui Wang. "Oxidation Behaviors of TiB₂-TiC_X and TiB₂-TiC_X/15SiC Ceramics." Advanced Materials Research 105-106 (April 2010): 179–83. http://dx.doi.org/10.4028/www.scientific.net/amr.105-106.179.

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Fully dense samples of TiB2-TiCX and TiB2-TiCX/15SiC ceramic composites were fabricated by in-situ synthesis under hot isostatic pressing from TiH2, B4C and SiC powders. Their oxidized behaviors at different temperatures were tested. Optical micrograph studies and thermo-gravimetric analyses show that the highest effective temperature of oxidation resistance is 700°C for TiB2-TiCX, and 1100°C for TiB2-TiCX/15SiC. The weight gain of TiB2-TiCX/15SiC below 1100°C is quite low, and it rises up suddenly when the temperature reaches 1200°C. Thus, the highest effective temperature of oxidation resistance is 1100°C for TiB2-TiCX/15SiC. The oxidation dynamic curves of TiB2-TiCX/15SiC ceramics accord with the parabola’s law. The activation energy of TiB2-TiCx/15SiC (189.87kJ.mol-1) is higher than that of TiB2-TiCx (96.44kJ.mol-1). In the oxidation process of TiB2-TiCx/15SiC, TiB2 reacts with oxygen and generates TiO2 and B2O3 at first. A layer of whole homogeneous oxide film cannot be formed, in the mean time, the oxidation of TiC begins. When temperature goes up to 1000°C, TiC phase is totally oxidized. SiC is oxidized to SiO2 at about 900°C, Meanwhile, TiO2 forms denser film than B2O3, which grows and covers the surface of the material, and gives better property of oxidation resistance.

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Goshkoderya, M. E., T. I. Bobkova, S. P. Bogdanov, A. V. Krasikov, M. V. Staritsyn, and A. A. Kashirina. "Spraying wear-resistant coatings from clad powders TiB2/Ti and HfB2/Ti." Izvestiya. Ferrous Metallurgy 66, no. 1 (February 20, 2023): 27–34. http://dx.doi.org/10.17073/0368-0797-2023-1-27-34.

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The present work considers the results on synthesis of composite clad powder systems with the “core-shell” type of structure for spraying wear-resistant metal-ceramic coatings. Powders of highly hard TiB2 and HfB2 borides were used as a core for the synthesis of a composite powder, and titanium was used to create coating on their surface. The cladding layer is synthesized by the iodine transport method. Powder cladding uses the method of detecting one component on another gas transport path, the agent of which is contact iodine. The deposition of composite clad powders of the TiB2 /Ti and HfB2 /Ti systems is implemented by the microplasma method, which, in contrast to the classical plasma deposition, makes it possible to dissolve transformations in composite powders due to thermal action. In the study of transverse microsections of sprayed coatings, it was found that during microplasma spraying, titanium is saturated with oxygen, forming a titanium dioxide phase, as a result of which the clad composite powder of systems TiB2 /Ti and HfB2 /Ti are converted into coatings from systems TiB2 (TiB)/Ti(TiO2 ) and HfB2 /Ti(TiO2 ). Features of the composition in terms of coating thickness were revealed. The study of hardness shows that the integral value of microhardness for a coating based on titanium diboride is 1300 HV. Coating based on hafnium diboride has integral microhardness of about 1600 HV. When checking the wear resistance, pairs with TiB2 (TiB)/Ti(TiO2 ) and HfB2 /Ti(TiO2 ) coatings were mated with a counterbody from the 45Kh sample without coatings and together with each other. Despite the lower microhardness, the most wear-resistant is coating of TiB2 (TiB)/Ti(TiO2 ) system.

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Svec, Pavol, Zuzana Gábrisová, and Alena Brusilová. "Reactive sintering of B4c-TiB2 composites from B4 and TiO2 precursors." Processing and Application of Ceramics 14, no. 4 (2020): 329–35. http://dx.doi.org/10.2298/pac2004329s.

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The effect of sintering temperature in the interval from 1775 to 1850?C on the density, microstructure, hardness and fracture toughness of ceramic composites consisting of a boron carbide matrix and titanium diboride secondary phase was studied. The composites were hot pressed using in situ reaction between boron carbide and 40 wt.% of titanium dioxide additive. The samples were hot pressed at different temperatures but for the constant time of 60min, under the pressure of 35MPa in vacuum of 10 Pa. Both Vickers hardness and fracture toughness of the composites increased with the sintering temperature.Maximal hardness of 29.8GPa and fracture toughness of 6.9MPa?m1/2 were achieved for the composite with 29.6 vol.% of titanium diboride secondary phase sintered at the highest sintering temperature of 1850?C.

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Svec, Pavol, Zuzana Gábrisová, and Alena Brusilová. "Reactive sintering of B4c-TiB2 composites from B4 and TiO2 precursors." Processing and Application of Ceramics 14, no. 4 (2020): 329–35. http://dx.doi.org/10.2298/pac2004329s.

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The effect of sintering temperature in the interval from 1775 to 1850?C on the density, microstructure, hardness and fracture toughness of ceramic composites consisting of a boron carbide matrix and titanium diboride secondary phase was studied. The composites were hot pressed using in situ reaction between boron carbide and 40 wt.% of titanium dioxide additive. The samples were hot pressed at different temperatures but for the constant time of 60min, under the pressure of 35MPa in vacuum of 10 Pa. Both Vickers hardness and fracture toughness of the composites increased with the sintering temperature.Maximal hardness of 29.8GPa and fracture toughness of 6.9MPa?m1/2 were achieved for the composite with 29.6 vol.% of titanium diboride secondary phase sintered at the highest sintering temperature of 1850?C.

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Shajari, Shayeste, Elaheh Kowsari, Naemeh Seifvand, Farshad Boorboor Ajdari, Amutha Chinnappan, Seeram Ramakrishna, Gopalan Saianand, Mohammad Dashti Najafi, Vahid Haddadi-Asl, and Soheil Abdpour. "Efficient Photocatalytic Degradation of Gaseous Benzene and Toluene over Novel Hybrid PIL@TiO2/m-GO Composites." Catalysts 11, no. 1 (January 15, 2021): 126. http://dx.doi.org/10.3390/catal11010126.

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In this work, the PIL (poly ionic liquid)@TiO2 composite was designed with two polymerized ionic liquid concentrations (low and high) and evaluated for pollutant degradation activity for benzene and toluene. The results showed that PIL (low)@TiO2 composite was more active than PIL (high)@TiO2 composites. The photodegradation rate of benzene and toluene pollutants by PIL (low)@TiO2 and PIL (high)@TiO2 composites was obtained as 86% and 74%, and 59% and 46%, respectively, under optimized conditions. The bandgap of TiO2 was markedly lowered (3.2 eV to 2.2 eV) due to the formation of PIL (low)@TiO2 composite. Besides, graphene oxide (GO) was used to grow the nano-photocatalysts’ specific surface area. The as-synthesized PIL (low)@TiO2@GO composite showed higher efficiency for benzene and toluene degradation which corresponds to 91% and 83%, respectively. The resultant novel hybrid photocatalyst (PIL@TiO2/m-GO) was prepared and appropriately characterized for their microstructural, morphology, and catalytic properties. Among the studied photocatalysts, the PIL (low)@TiO2@m-GO composite exhibits the highest activity in the degradation of benzene (97%) and toluene (97%). The ultimate bandgap of the composite reached 2.1 eV. Our results showed that the as-prepared composites hold an essential role for future considerations over organic pollutants.

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Ahmad, Nur, Alfan Wijaya, Amri Amri, Erni Salasia Fitri, Fitri Suryani Arsyad, Risfidian Mohadi, and Aldes Lesbani. "Catalytic Oxidative Desulfurization of Dibenzothiophene by Composites Based Ni/Al-Oxide." Science and Technology Indonesia 7, no. 3 (July 28, 2022): 385–91. http://dx.doi.org/10.26554/sti.2022.7.3.385-391.

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In the present study, composite layer double hydroxide-metal oxide (Ni/Al-TiO2 and Ni/Al-ZnO) was successfully prepared and used as catalyst of oxidative desulfurization of dibenzothiophene. Characterization of catalyst was used XRD, FTIR, and SEM-EDS. The structure of Ni/Al-LDH, TiO2, and ZnO in composite Ni/Al-TiO2 and Ni/Al-ZnO was consistent, which also indicated that the preparation of composite did not change the form of precursors. FTIR spectra of Ni/Al-TiO2 and Ni/Al-ZnO absorption band at 3398, 1639, 1339, 832, 731, and 682 cm−1. The catalysts have an irregular structure, TiO2 and ZnO adhere to the surface of Ni/Al LDH. The percent mass of Ti and Zn on the composite at 29.3% and 18.2%, respectively. The acidity of Ni/Al LDH increased after being composited with TiO2 and ZnO. The optimum reaction time, dosage catalyst, and temperature were 30 min, 0.25 g, and 50°C, respectively, and n-hexane as a solvent. The percentage conversion of dibenzothiophene on Ni/Al-LDH, TiO2, ZnO, Ni/Al-TiO2, and Ni/Al-ZnO were 99.44%, 91.92%, 95.36%, 99.88%, and 99.90%, respectively. The catalysts are heterogeneous system and the advantage is that can be used for reusability. After 3 times catalytic reactions, the conversion of dibenzothiophene still retains more than 80%, even Ni/Al-TiO2 and Ni/Al-ZnO composites still 97.79% and 98.99%, respectively.

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Kumar, G. B. Veeresh, P. S. Shivakumar Gouda, R. Pramod, and C. S. P. Rao. "Synthesis and Characterization of TiO2 Reinforced Al6061 Composites." Advanced Composites Letters 26, no. 1 (January 2017): 096369351702600. http://dx.doi.org/10.1177/096369351702600104.

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This article presents the investigative work carried out to study the relationship between the physical, mechanical and tribological characteristics of aluminum matrix composites reinforced with Titanium dioxide (TiO2). The powder metallurgy route of production was followed to produce the composites (Al6061 containing 3 wt% TiO2). The composites were subjected to sequences of physical, mechanical and tribological investigations. The outputs of the experiments done indicate that the increase in TiO2 fillers increase the density of the composite and the values accepted by the rule of mixtures. The result of mechanical characterisation of Al6061-TiO2 composites was noticed to increase significantly with higher TiO2 content in the matrix, with loss in ductility. The dry sliding wear studies of Al6061-TiO2 composite showed greater wear resistance than Al6061 matrix and the composite containing higher filler content displayed the superior physical, mechanical and tribological characteristics.

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22

Li, Pengfei, Minxian Shi, Zongyi Deng, Pengkun Han, Tingli Yang, Rui Hu, Chuang Dong, Rui Wang, and Jie Ding. "Achieving excellent oxidation resistance and mechanical properties of TiB₂–B₄C/carbon aerogel composites by quick-gelation and mechanical mixing." Nanotechnology Reviews 11, no. 1 (January 1, 2022): 3031–41. http://dx.doi.org/10.1515/ntrev-2022-0489.

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Abstract Thermal protection system (TPS) is of great significance to launch hypersonic flight and landing process of hypersonic vehicles, which can effectively shield the hypersonic vehicle from severe aerodynamic heating encountered. Phenolic aerogels play an important role in TPS due to their characteristics of low density, high porosity, and low thermal conductivity. However, phenolic aerogel is easy to be oxidized at elevated temperatures under oxidizing environments, which severely limits its large-scale application as thermal insulation materials in TPS. In this study, a novel TiB2–B4C/carbon (TB/C) aerogel composite was synthesized by introducing TiB2 and B4C particles into phenolic aerogels through quick-gelation and mechanical mixing. The developed aerogel composites were characterized by scanning electron microscopy, Fourier transform infrared, thermal analysis, etc., to evaluate their microstructure, oxidation resistance, and mechanical properties. Experimental evidence showed that TiB2 and B4C particles reacted with the oxygen-containing molecules to form TiO2–B2O3 layer, which effectively improved oxidation resistance and mechanical properties of phenolic aerogel composites.

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23

Heltina, D., N. Adharianti, D. G. Randa, and Komalasari. "Effect of Adding Fe₃O₄ in Graphene/TiO₂/Fe₃O₄ Composite for Phenol Photodegradation Application." Journal of Physics: Conference Series 2049, no. 1 (October 1, 2021): 012089. http://dx.doi.org/10.1088/1742-6596/2049/1/012089.

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Abstract In order to improve the performance of TiO2, a material that can increase the adsorption ability of TiO2 is needed, one of which is graphene. Graphene/TiO2 composites can be used to degrade phenol. The addition of a magnet material to the grapene/TiO2 composite, namely Fe3O4 is expected to facilitate the separation of the catalyst after being used in the phenol degradation process. This study aims to synthesize and characterize graphene/TiO2/Fe3O4 composites. The composite obtained was used to degrade phenol. This research begins with the modification of graphene with the surfactant cocoPAS. Synthesis of graphene/TiO2/Fe3O4 composite with various amount of Fe3O4 in composite (0.3, 0.5 and 0.7 g, respectively). Composites used for phenol degradation and separated after degradation. The composite materials were characterized by the scanning electron microscopy (SEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific surface areas, Fourier transform infrared (FT-IR) and UV-vis absorption spectroscopy. Graphene/TiO2/Fe3O4 composite with a mass of Fe3O4 in the composite of 0.3 g indicates the highest degradation, while the catalyst separation process after phenol degradation showed the fastest time in the separation of the Fe3O4 mass in the composite, which was 0.5 g. the faster the separation time required, but the performance of the composite in degrading phenol is decreasing.

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24

Loganathan, P., A. Gnanavelbabu, K. Rajkumar, and S. Ayyanar. "Microstructural Characteristics and Mechanical Behaviour of AA7075/TiB₂ Composite." Materials Science Forum 979 (March 2020): 40–46. http://dx.doi.org/10.4028/www.scientific.net/msf.979.40.

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Titanium Boride (TiB2) particles reinforced with aluminum alloy (AA 7075) composites were developed using the two-step stir casting method. TiB2 with aluminium alloy was varied in 5, 10, 15 weight percentages (wt.%) . The mechanical properties of the composites were assessed through density, hardness, tensile and impact. Factography observations were also evaluated with Scanning Electron Microscopy (SEM) and phase identification of the composite was carried out through X-ray diffraction technique (XRD). The XRD pattern of alloy and composites revealed peaks of Al and TiB2 particles and the intensity of TiB2 particles increased with increase in wt. %. Compared to the base matrix, the density and hardness of composites increased with the wt. % of TiB2. Addition of TiB2 particles exhibited grain refinement, thereby improving the mechanical properties. Composite materials exhibited high load bearing capacity due to the strong bonding of TiB2 and matrix material resulting in increased impact energy. The tensile strength of the composite increased with increasing wt. % of reinforcement. The failure in the composites observed were dimpled structure and ridges, voids, and cracks.

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Pan, Xiaoyan. "Study on preparation and properties of nanocrystalline TiO₂/graphite photocatalytic composite by mechanochemistry." Journal of Physics: Conference Series 2539, no. 1 (July 1, 2023): 012057. http://dx.doi.org/10.1088/1742-6596/2539/1/012057.

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Abstract Graphite-modified TiO2 composite is a promising photocatalyst in environmental purification. In this study, TiO2/graphite photocatalytic composites were prepared by mechanochemistry using natural flake graphite and nanocrystalline TiO2 as raw materials. The composites were examined by X-ray diffractometer, Raman spectrometer, X-ray photoelectron spectrometer, scanning electron microscope and UV-vis spectrophotometer. The photoelectrochemical properties of the composites were investigated via electrochemical impedance spectroscopy and photocurrent response. The influences of the content and premilling time of graphite on the photocatalytic properties of the composites were studied through the photocatalytic decomposition of methylene blue. The results showed that graphite was exfoliated and broken during ball milling, and defects of graphite increased with the extension of milling time. In the composite, there is no solid solution of carbon atoms in TiO2 lattice. The photocatalytic results indicated that a proper amount of graphite could improve the photocatalytic behavior of TiO2. The TiO2/graphite composite containing 1wt% graphite exhibited the best photocatalytic behavior. The pretreatment of graphite by ball milling could enhance the photocatalytic behavior of the TiO2/graphite composite and the optimal premilling time of graphite was 4 hours.

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26

Zhu, He Guo, Jin Min, Da Chu, and Huan Wang. "Study on the Reaction Mechanism of (α-Al₂O₃+TiB₂+TiC)/Al Composites Fabricated by Al-TiO₂-B₄C System." Advanced Materials Research 150-151 (October 2010): 84–87. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.84.

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The composites (-Al2O3+TiB2+TiC)/Al has been fabricated by using exothermic dispersion synthesis. Thermodynamic analysis indicated that the reaction between the Al and TiO2 can spontaneously occur due to the negative Gibbs free energy of the Al-TiO2 reaction system. With the increase of B4C/TiO2 mole ratios, the exothermic peaks increase move to the higher temperature and the corresponding ignite temperatures also increase. The reaction results indicate that when the B4C/TiO2＝0, the reinforcements are composed of -Al2O3, Al3Ti, with the increase of B4C/TiO2, the amount of Al3Ti decreases and the TiC and TiB2 form simultaneously. When the B4C/TiO2 increases to 1/3, the Al3Ti almost disappear and the reinforcements of the composites are consisted of -Al2O3, TiC and TiB2.

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27

Sagara, Katsuhiro, Yun Lu, and Dao Cheng Luan. "FEM Analysis on Thermoelectric Properties of Metal/TiO_2–x Composites with Random Distribution of Metal Powder." Materials Science Forum 750 (March 2013): 130–33. http://dx.doi.org/10.4028/www.scientific.net/msf.750.130.

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Analysis model of finite element method with a random distribution for thermoelectric composites was built. Thermoelectric properties including electrical resistivity, Seebeck coefficient and thermal conductivity of M/TiO2–x (M = Cu, Ni, 304 stainless steel (304SS)) thermoelectric composites were investigated by the proposed model. Cu/TiO2–x composite showed a large decrease in electrical resistivity while 304SS/TiO2–x composite thermal conductivity was slightly increased. Calculated dimensionless figure-of-merit, ZT of Ni/TiO2–x composite was higher than those of TiO2–x and the other composites in a wide range of metal volume fractions because Ni has large absolute values of Seebeck coefficient, power factor and dimensionless figure-of-merit compared to the other two metals. It was found that power factor and dimensionless figure-of-merit of thermoelectric composites depended on the balance among electrical resistivity, thermal conductivity and Seebeck coefficient. The results revealed that it is important for M/TiO2–x composites to choose suitable addition metal with high power factor and dimensionless figure-of-merit.

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Mirjalili, Abolfazl, Ali Zamanian, and Seyed Mohammad Mahdi Hadavi. "The effect of TiO2 nanotubes reinforcement on the mechanical properties and wear resistance of silica micro-filled dental composites." Journal of Composite Materials 53, no. 23 (December 19, 2018): 3217–28. http://dx.doi.org/10.1177/0021998318818882.

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One of the most important aspects of dental resin composites is the ability to improve mechanical properties by adding reinforcing filler particles. TiO2 nanotubes are expected to improve the physical and mechanical properties of silica micro-filled dental composite. Therefore, TiO2 nanotubes were synthesized using an alkaline hydrothermal process and then functionalized with 3-methacryloxypropyl-trimethoxysilane. TiO2 nanotubes were characterized by scanning and transmission electron microscopies, X-ray diffraction and Fourier transform infrared spectroscopy. Different quantities of TiO2 nanotubes and silica microparticles were reinforced in bisphenol A-glycidyl methacrylate (Bis-GMA) and tri-ethylene glycol dimethacrylate to prepare dental composite samples. Thereafter, the flexural strength and modulus, compressive strength, degree of conversion of monomers, wear resistance and water sorption were utlized to examine the prepared composites. The flexural strength and wear resistance of composites with 3 wt% TiO2 nanotubes significantly increased in comparison with other composites. On the other hand, due to the stability of composite, the water sorption was decreased. Therefore, TiO2 nanotubes reinforcement could be a promising solution for the improvement of mechanical properties in dental composites.

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29

Butylina, Svetlana, Ossi Martikka, and Timo Kärki. "Effect of inorganic pigments on the properties of coextruded polypropylene-based composites." Journal of Thermoplastic Composite Materials 31, no. 1 (April 28, 2016): 23–33. http://dx.doi.org/10.1177/0892705716646416.

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In this article, the effect of the incorporation of three inorganic pigments on the properties of coextruded polypropylene-based composites was studied. Three different pigments were incorporated in the shell layer of the composites: iron oxide, titanium dioxide (TiO2) and zinc oxide (ZnO). The tensile properties and Charpy impact strength of the composites were tested. A water immersion test was conducted. The morphology of the fractured surfaces of composites was characterised by scanning electron microscopy. The durability of the composites was assessed by testing colour characteristics and tensile strength after 500 hours of accelerated weathering. The results revealed that the TiO2-containing composite had the highest tensile modulus and Charpy impact strength, while the ZnO-containing composite had the lowest tensile strength and Charpy impact strength. Iron oxide was found to have no effect on either the physical or mechanical properties of the composite. The porosity of composites influences their water absorption and thickness swelling. The TiO2-containing composite exhibited better colour stability.

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30

Zhao, Shu Mao, and Ling Ran Zhao. "Mechanical Properties of Hot-Pressed B4C-TiB2 Composites Synthesized from B4C-TiO2 and B4C-TiC." Key Engineering Materials 902 (October 29, 2021): 81–86. http://dx.doi.org/10.4028/www.scientific.net/kem.902.81.

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In this study, B4C-TiB2 ceramic composites were manufactured by hot pressing method. The raw materials for the in-situ synthesis of TiB2 were TiO2 and TiC. After being sintered at 1900°C for 60min under a pressure of 30MPa, compact composites samples with a TiB2 volume fraction range from 0 to 11.05% were prepared. The relative density, fracture toughness and flexural strength of different sample were tested. Microstructures on the fracture surface were studied by SEM. The result shows that B4C-TiB2 ceramic composites sintered from B4C-TiC had a better mechanical property than the one sintered from B4C-TiO2. When the content of TiB2 (reacted from TiC) was 11.05vol.%, the strength and toughness of B4C-TiB2 ceramics can reach 598MPa and 6.45MPa·m1/2. The toughening mechanisms of B4C-TiB2 composites include micro-crack toughening and energy consumption by the pulling out process of second phase.

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Cheng, Eric Jian Feng, Hirokazu Katsui, and Takashi Goto. "Lamellar and Rod-Like Eutectic Growth of TiB₂-TiC-TiN Composites by Arc-Melting." Key Engineering Materials 616 (June 2014): 43–46. http://dx.doi.org/10.4028/www.scientific.net/kem.616.43.

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TiB2-TiC, TiB2-TiN and TiB2-TiCxN1-x composites were prepared by arc-melting mixtures of TiB2, TiC and TiN powders. 28TiB2-72TiC (mol%) composite showed a lamellar eutectic structure, while 55TiB2-45TiN (mol%) composite with a lamellar structure consisted of TiB2, TiN and TiB. 36TiB2-44TiC-20TiN (mol%) was a quasi-binary eutectic composite having a rod-like structure.

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32

Luo, Yue, Xue Min Yan, Huan Yang, and Gao Shen Su. "Hydrothermal Synthesis and Adsorption Proprieties of Titania-Active Carbon Composites." Advanced Materials Research 150-151 (October 2010): 391–95. http://dx.doi.org/10.4028/www.scientific.net/amr.150-151.391.

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Titania nanoparticles were anchored onto active carbon (AC) through a hydrothermal process to obtain TiO2/AC composites. The optimal TiO2 loading and hydrothermal pH were investigated. The prepared TiO2/AC composites were used as adsorbents for dibenzothiophene (DBT) from model fuel. The adsorption capacity of TiO2/AC composite in the optimal synthesis conditions has enhanced 12.4% compared with pure AC. The adsorbents were regenerated by toluene washing, and the TiO2/AC composite showed higher adsorptive capacity than AC even after three recycles. The pore structure and surface chemical proprieties of TiO2/AC composite and AC were also investigated by N2 adsorption-desorption isotherms and Beohm titration. The results indicate that the surface acidic sites of TiO2/AC may play an important role in the improved adsorption performance.

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33

Amirzade-Iranaq, Mohammad Taher, Mahdi Omidi, Hamid Reza Bakhsheshi-Rad, Abbas Saberi, Somayeh Abazari, Nadia Teymouri, Farid Naeimi, et al. "MWCNTs-TiO2 Incorporated-Mg Composites to Improve the Mechanical, Corrosion and Biological Characteristics for Use in Biomedical Fields." Materials 16, no. 5 (February 25, 2023): 1919. http://dx.doi.org/10.3390/ma16051919.

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This study attempts to synthesize MgZn/TiO2-MWCNTs composites with varying TiO2-MWCNT concentrations using mechanical alloying and a semi-powder metallurgy process coupled with spark plasma sintering. It also aims to investigate the mechanical, corrosion, and antibacterial properties of these composites. When compared to the MgZn composite, the microhardness and compressive strength of the MgZn/TiO2-MWCNTs composites were enhanced to 79 HV and 269 MPa, respectively. The results of cell culture and viability experiments revealed that incorporating TiO2-MWCNTs increased osteoblast proliferation and attachment and enhanced the biocompatibility of the TiO2-MWCNTs nanocomposite. It was observed that the corrosion resistance of the Mg-based composite was improved and the corrosion rate was reduced to about 2.1 mm/y with the addition of 10 wt% TiO2-1 wt% MWCNTs. In vitro testing for up to 14 days revealed a reduced degradation rate following the incorporation of TiO2-MWCNTs reinforcement into a MgZn matrix alloy. Antibacterial evaluations revealed that the composite had antibacterial activity, with an inhibition zone of 3.7 mm against Staphylococcus aureus. The MgZn/TiO2-MWCNTs composite structure has great potential for use in orthopedic fracture fixation devices.

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34

Gemelli, Enori, Patrícia Borges da Silva Maia, Fabio Nery, Nelson Heriberto Almeida Camargo, Vinícius André Rodrigues Henriques, Jailson de Jesus, and Priscila Ferraz Franczak. "Effect of Calcium Titanate and/or Titanium-Phosphides in the Properties of Titanium Composites for Implant Materials." Advanced Materials Research 906 (April 2014): 226–31. http://dx.doi.org/10.4028/www.scientific.net/amr.906.226.

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Titanium-based composites containing TixPy phase (s) or CaTiO3 and TixPy phase (s) were produced by a non conventional method using suitable mixtures of TiH2 powder and phosphoric acid (TiH2/P), or TiH2 and 10 vol.% of calcium phosphate (TiH2/CP), respectively. The composites were produced with the same phosphor molar concentration. The mixtures were prepared by ultrasound in water, dried in a rotary evaporator, pressed at 600 MPa and vacuum-sintered at 1200 °C for 2 hours. The mixtures were well dispersed by ultrasound and agglomerate-free. The analyses show that titanium particles were coated with TixPy phase (s) for the TiH2/P composite or with an intermediary layer of TixPy phase (s) and an external deposit of calcium titanate for the TiH2/CP composite. The TiH2/P composite presented higher compressive strength and about the same contact angle compared to the TiH2/CP composite. However, both materials displayed lower contact angle than that of pure titanium.

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35

Pijarn, Nuchanaporn, Hasan Seng, Tuwaeibroheng Toso, and Chanatan Dissong. "TiO₂-SiO₂ Gel Photocatalytic Degradation of Methylene Blue and Composite Energy Gap Calculation." Key Engineering Materials 706 (August 2016): 94–98. http://dx.doi.org/10.4028/www.scientific.net/kem.706.94.

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The objectives of this study were to mix TiO2 and SiO2 gel for photo catalyzing in methylene blue and calculated energy gap of TiO2- SiO2 gel composite. Nanoparticles of TiO2-doped SiO2 gels have been synthesized for use as composites in photodegradation of methylene blue. SiO2 gel was synthesized by a sol-gel method from rice husk ash. TiO2 was synthesized by microwave method from TiOSO4. The composite of TiO2-SiO2 was prepared by mixing of 25% wt TiO2 and 75% wt SiO2 gel and SiO2 gel bead. This work can be dived into two kinds of TiO2 sources were TiO2 from microwave synthesis (MW) and TiO2 from P25. The UV absorption values of methylene blue after used TiO2-SiO2 composite were measured. Wavelengths of composites were measured by Uv-vis reflectometer and energy gap were calculated.

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36

Li, Zhaoqing, Zhufeng Liu, Xiao Yang, Annan Chen, Peng Chen, Lei Yang, Chunze Yan, and Yusheng Shi. "Enhanced Photocatalysis of Black TiO2/Graphene Composites Synthesized by a Facile Sol–Gel Method Combined with Hydrogenation Process." Materials 15, no. 9 (May 6, 2022): 3336. http://dx.doi.org/10.3390/ma15093336.

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In this study, in situ TiO2 was grown on the surface of graphene by a facile sol–gel method to form black TiO2/graphene composites with highly improved photocatalytic activity. The combination of graphene and TiO2 was beneficial to eliminate the recombination of photogenerated electron holes. The self-doping Ti3+ was introduced, accompanied by the crystallization of amorphous TiO2, during the hydrogenation process. Consequently, the narrowed bandgap caused by self-doping Ti3+ enhanced the visible light absorption and thus made the composites appear black. Both of them improved the photocatalytic performance of the synthesized black TiO2/graphene composites. The band structure of the composite was analyzed by valence band XPS, revealing the reason for the high visible light catalytic performance of the composite. The results proved that the black TiO2/graphene composites synthesized show attractive potential for applications in environmental and energy issues.

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Zhao, Guo Long, Chuan Zhen Huang, Han Lian Liu, Bin Zou, Hong Tao Zhu, and Jun Wang. "Synthesis of Al₂O₃ Ceramics Matrix Composites by Thermal Explosion under Pressure and Hot Pressing." Advanced Materials Research 690-693 (May 2013): 534–37. http://dx.doi.org/10.4028/www.scientific.net/amr.690-693.534.

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Three kinds of Al2O3 ceramics matrix composites, such as Al2O3-TiB2, Al2O3-SiC and Al2O3-TiC, were prepared by two steps, which were synthesis of the composites by thermal explosion under a pressure of 20MPa and hot pressing of the composites at 1700°C under a pressure of 32MPa respectively. The preparation process, the composition and the microstructure of the composites were investigated in detail. The Gibbs free energy and the adiabatic temperature (Tad) of three exothermic synthesis reactions were calculated. Disc-shaped and elongated TiB2 grains were synthesized in the Al2O3-TiB2 composite. Some whiskers and platelet grains were synthesized in the Al2O3-SiC composite. Nano-particles were synthesized in the Al2O3-TiC composite and distributed both within the Al2O3 matrix grains and along the grain boundaries.

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38

Wahyuni, Sri, Eko Sri Kunarti, Respati Tri Swasono, and Indriana Kartini. "Characterization and Photocatalytic Activity of TiO₂(rod)-SiO₂-Polyaniline Nanocomposite." Indonesian Journal of Chemistry 18, no. 2 (May 30, 2018): 321. http://dx.doi.org/10.22146/ijc.22550.

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A study of TiO2(rod)-SiO2 composites coated with polyaniline (PANI) has been performed. PANI was synthesized through in-situ polymerization of aniline at various concentration (0.0137, 0.0274, and 0.0411 M) on the composite under acidic condition. PANI was confirmed by the appearance of C=N, C=C vibrations and the redshift of the band-gap from 3.14 eV for the TiO2(rod)-SiO2 into 3.0 eV for the TSP01 composite. It is also shown that the polymerization does not change the crystal structure of TiO2(rod)-SiO2 as confirmed by the XRD pattern. The TEM image shows a mixed structure of SiO2 coated by TiO2(rod)-PANI layers and the oxides coated by PANI layers. Therefore, the surface area of the resulted TiO2(rod) and the composites did not change significantly. The T TiO2(rod)-SiO2-PANI composite give small improvement under visible irradiation from 20.25 to 25.59% (around 5% from the bulk of TiO2(rod)) and from 25.03 to 25.59% (around 2% from TiO2(rod)-SiO2 composite). The mixed structure of the composites, as well as the formation of excessive layers of PANI, are possibly the case for the low photoactivity. Further improvement to obtain a core-shell structure with a thin layer of PANI is still sought.

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39

Jang, Myung Geun, Choonglai Cho, and Woo Nyon Kim. "Synergistic effects of hybrid conductive fillers on the electrical properties of carbon fiber pultruded polypropylene/polycarbonate composites prepared by injection molding." Journal of Composite Materials 51, no. 7 (July 28, 2016): 1005–17. http://dx.doi.org/10.1177/0021998316658536.

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In this study, the effects of filler characteristics and composite preparation methods on the morphology, mechanical property, electrical conductivity, and electromagnetic interference shielding effectiveness of the polypropylene/polycarbonate (70/30, wt%)/hybrid conductive filler composites were investigated. Nickel-coated carbon fiber (NCCF) was used as main filler and TiO2, multi-walled carbon nanotube, and graphite were used as second fillers in the composites. The pultruded NCCF/polypropylene composite was used in the preparation of the polypropylene/polycarbonate/NCCF/second filler composites. The electrical conductivity and electromagnetic interference shielding effectiveness of the polypropylene/polycarbonate/NCCF/second filler composites were compared with the type of second filler. The superior value of electromagnetic interference shielding effectiveness was observed to be 51.6 dB (decibel) when the hybrid fillers such as NCCF (5.2 vol% or 20 wt%) and TiO2 (1.2 vol% or 5 wt%) were added in the polypropylene/polycarbonate (70/30) composite. The electrical properties of the polypropylene/polycarbonate (70/30)/NCCF/TiO2 composites was compared with the composite preparation methods, which were injection molding and screw extrusion. The results suggested that fiber length of the NCCF affected significantly to the electrical conductivity and electromagnetic interference shielding effectiveness of the polypropylene/polycarbonate (70/30)/NCCF/TiO2 composites.

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40

Xu, Geng-fu, Yuval Carmel, Tayo Olorunyolemi, Isabel K. Lloyd, and Otto C. Wilson. "Microwave sintering and properties of AlN/TiB2 composites." Journal of Materials Research 18, no. 1 (January 2003): 66–76. http://dx.doi.org/10.1557/jmr.2003.0010.

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The effect of TiB2 on the densification behavior and properties of microwave-sintered AlN/TiB2 ceramic was investigated. The densification of the composite was significantly retarded in nitrogen atmosphere due to strong nitridation of TiB2 compared to sintering in argon atmosphere. The densities of the AlN/TiB2 composites containing different amounts of TiB2 all reached 99% of the theoretical density during 2 h of sintering at 1850 and 1900 °C. Microstructure analysis revealed that the TiB2 particles were dispersed in the AlN matrix while AlN grains retained its contiguity. This microstructure led to a composite with superior properties; thermal conductivity as high as 149 W/(m K) was achieved. The microwave sintered composites are harder and tougher than pure AlN. Microwave-sintered AlN/TiB2 composite is a promising material for structural applications in which high thermal conductivity and controlled dielectric loss are important.

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41

Kikitsu, Shin Ichi, Takaaki Otsuka, Hidetoshi Miyazaki, Hisao Suzuki, and Toshitaka Ota. "Fabrication and Evaluation of Arrayed Needle-Like TiO₂ Particle – Transparent Resin Composite Films." Key Engineering Materials 484 (July 2011): 177–82. http://dx.doi.org/10.4028/www.scientific.net/kem.484.177.

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Needle-like TiO2-resin composite films were fabricated using needle-like TiO2 particle filler and urethane matrix. The needle-like TiO2 particles in the composite film were arrayed completely under the fabrication condition of applying AC bias of 10 volt with 0.1 Hz for 4 hr, and the transmittance of the resulting composite film showed angularly dependence. The needle-like TiO2 particles in the composite were oriented quickly by a larger applying bias. Furthermore, increase of the mixing ratio of TiO2 particles in the composite film caused increasing an angularly dependence of the transmittance of the composites.

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42

Lv, Yanan, Tao Li, Honglei Zhao, Xuepeng Li, Ying Bu, and Yongxia Xu. "Preparation of nano-TiO2 composite photocatalytic material and its degradation performance on aldehydes." E3S Web of Conferences 213 (2020): 01009. http://dx.doi.org/10.1051/e3sconf/202021301009.

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Chitosan-TiO2 photocatalytic composite was prepared using anatase nano-TiO2 and edible chitosan. Fourier Transform Infrared Spectroscopy (FT-IR), ultraviolet visible (UV-vis) and scanning electron microscopy (SEM) was used to characterize the structure of the composites. The photocatalytic degradation performance of the composites was studied by constructing a simulation system. The stability of the combination between chitosan and TiO2 in the composite can be confirmed by the results of FT-IR, UV-vis and SEM. The composite had a good photocatalytic degradation effect. When the addition amount of chitosan-TiO2 was 0.4%, the degradation efficiency of heptanal, octanal, (E)-2-heptenal and (E)-2-octenal reached the highest values of 83.82%, 81.73%, 96.33% and 93.36%, respectively.

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43

Wei, Fengjun, Bingli Pan, and Juan Lopez. "The tribological properties study of carbon fabric/ epoxy composites reinforced by nano-TiO2 and MWNTs." Open Physics 16, no. 1 (December 31, 2018): 1127–38. http://dx.doi.org/10.1515/phys-2018-0133.

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Abstract A kind of carbon fabric/epoxy composite was successfully prepared with carbon fiber fabric as reinforced phase and epoxy resin as binder phase, then the nano-TiO2 and a hybrid system of TiO2/MWNTs was added into the carbon fabric/ epoxy composite matrix respectively to prepare a kind of nano-composite. The friction and wear properties of CF/EP composites under different load conditions have been studied in this article, during the study the effects of filler types and contents on the tribological properties were researched, at last the worn surfaces were investigated and the abrasion mechanism was discussed. The results showed that: whether filling the nano-TiO2 alone or mixing the TiO2/MWNTs, it was able to achieve a good effect on decreasing friction and reducing wear, and the optimum addition ratio of the nano-TiO2 particles was 3.0% , meanwhile 3.0% of nano-TiO2 and 0.4% of MWNTs could cooperate with each other in their dimension, and could show a synergistic effect on modifying the tribological properties of CF/EP composites, the coefficient of friction of the modified composites decreased by 20% and the wear life increased by more than 140% compared with that of pristine composite materials, in the process of friction and wear, the wear form of the composites materials varied from brittle rupture to abrasive wear gradually.

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Liu, Xiongzhang, Xixi Li, Xue Lei, Deping Zhang, Zhijun Liu, Xueyuan Long, and Rongzhou Gong. "Research on dielectric and microwave absorbing properties of TiO₂/TiB₂/Thermoplastic polyurethanes (TPU) composite materials." Journal of Physics: Conference Series 2248, no. 1 (April 1, 2022): 012012. http://dx.doi.org/10.1088/1742-6596/2248/1/012012.

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Abstract TiO2/TiB2 materials are prepared by the carbothermal method and high-temperature calcination. Further, the phase composition, microstructure, dielectric and electromagnetic (EM) wave absorption characteristics are investigated. The results display that the product is composed of TiO2, TiB2 and impurity phases. The complex permittivity increases at elevated TiO2/TiB2 loading and slowly decreases with rising frequency in 2-18 GHz. When the TiO2/TiB2 content is 45 wt%, the minimum reflection loss (RLmin ) reaches -43.12 dB at 11.68 GHz with a thickness of 1.9 mm. The effective absorption band (EAB, RL<-10 dB) can reach 3.68 GHz at 2.3 mm as the TiO2/TiB2 content is 30 wt%. The enhanced EM wave absorption owes to the strong polarization loss and high conductivity loss. It goes without saying that TiO2/TiB2 materials can acquire important breakthroughs in the development of novel EM wave absorbers with outstanding absorption loss, wider EAB and smaller thicknesses.

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Ke, Ou Yang, Xie Shan, and Xiao Ou Ma. "Preparation and Characterization of Photocatalytic TiO₂/CdS Nanocomposite Loaded on Multi-Walled Carbon Nanotues (MWCNTs)." Applied Mechanics and Materials 184-185 (June 2012): 1114–19. http://dx.doi.org/10.4028/www.scientific.net/amm.184-185.1114.

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Multi-walled carbon nanotues (MWCNTs)/TiO2/CdS composite photocatalysts were prepared by sol–gel method in order to investigate its photocatalytic activity under simulated solar irradiation. MWCNTs/TiO2/CdS composite photocatalysts were characterized by the methods of SEM, XRD, TG and UV–vis. The results showed that MWCNTs/TiO2/CdS composites were mainly composed of anatase-TiO2 and little CdS cubic phases. the composite can cause an pronounced red shift of UV–vis spectra compared with pure TiO2. The degradation of MO by MWCNTs/TiO2/CdS composite photocatalysts under simulated solar light irradiation was studied. The results showd that the presence of MWCNTs and CdS can enhance the photoefficiency of TiO2.

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Ramesh, Balasubramanian, Essmat Showman, S. A. Muhammed Abraar, Kuldeep Kumar Saxena, Mohammed Y. Tharwan, Naif Alsaadi, Sharaf Al Sofyani, and Ammar H. Elsheikh. "Microstructure, Mechanical Characteristics, and Wear Performance of Spark Plasma Sintered TiB2–Si3N4 as Affected by B4N Doping." Materials 15, no. 20 (October 12, 2022): 7096. http://dx.doi.org/10.3390/ma15207096.

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This study aims to analyze the effect of boron nitride (B4N) additive (3–6%) on the densification, microstructure, mechanical properties, and wear performance of TiB2–15%Si3N4 and TiB2–30%Si3N4 sintered composites. When the B4N (3%) was added to the TiB2–30Si3N4 composite, the density increased to 99.5%, hardness increased to 25.2 MPa, and the fracture toughness increased to 4.62 MPam1/2. Microstructural analysis shows that in situ phases such as TiB2 help to improve the relative mechanical characteristics. However, raising the B4N additive to 6% in the above-sintered composite reduces the composites’ relative density and hardness. The tested sintered composites demonstrated that their superior wear resistance can be attributed to their increased density and hardness.

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Lü, Peng, Fang Yu, and Hong Qiang Ru. "A Comparison between B₄C-TiB₂-Al Composite and B₄C-Al Composite on Microstructure and Mechanical Properties." Applied Mechanics and Materials 66-68 (July 2011): 255–59. http://dx.doi.org/10.4028/www.scientific.net/amm.66-68.255.

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B4C-Al and B4C-TiB2-Al composites were fabricated by infiltrating aluminum into porous B4C and B4C-TiB2preforms in vacuum. The effect of TiB2addition on the microstucture and mechanical properties of the B4C-Al composites were investigated. The flexural strength and the fracture toughness of composite improved greatly as the result of TiB2addition. The TiB2addition inhibited the reaction between B4C and Al. The infiltrated aluminum addition was the leading reason for the fracture toughness improvement of the composites. Inter/transgranular fracture mode with many tear ridges and dimples was showing in the fracture surface of the B4C-TiB2-Al composite. The relationships between the microstructures and the mechanical properties of the B4C-TiB2-Al composites were discussed.

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Górny, Gabriela, Ludosław Stobierski, Paweł Rutkowski, and Marian Rączka. "Effect of Processing Conditions on Microstructure of SiC-TiB₂ Composite." Solid State Phenomena 197 (February 2013): 250–55. http://dx.doi.org/10.4028/www.scientific.net/ssp.197.250.

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The objective of the study as described in this paper is to analyse the effect of processing conditions as: volumetric content of TiB2 powders and the time of milling them on the parameters of microstructure of particulate composite with a SiC matrix and 10 or 20 vol.% of the TiB2 as dispersed phase. From the initial research conducted by the authors, as well as from the data contained in the reference literature, it is known that the SiC-TiB2 composite is a potential material to be applied in the manufacture of cutting tool inserts. To manufacture composites, SiC powders (Starck, UF-15) and TiB2 powders (Momentive, HCT-30) were used; they were milled for 15 or 30 h in a vibrating-rotating mill with silicon carbide balls as grinding media. The SiC-TiB2 composite was manufactured using a hot pressing method under the following conditions: temperature: 2120 oC; pressure: 25 MPa; and sintering time: 30 min. Under the stereological analysis of SiC-TiB2 some selected microstructural parameters were measured, i.e.: volume fraction of TiB2, average size of TiB2 particles, mean diameter of particles (D), shape factor of TiB2 particles, α, as well as NA and NV parameters that determine the quantity of TiB2 particles contained in the composite. Computer-aided analysis of microstructure of the SiC-TiB2 composites and analysis of results of measurements of mechanical properties of these composites prove their the microstructure and properties depend on the volumetric content of TiB2 dispersed phase, and this dependence is significant.

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Wang, Guo Feng, Ji Hong Zhang, Chunping Zhang, and Kai Feng Zhang. "Densification and Mechanical Properties of B₄C Based Composites Sintered by Reaction Hot-Pressing." Key Engineering Materials 434-435 (March 2010): 24–27. http://dx.doi.org/10.4028/www.scientific.net/kem.434-435.24.

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Boron carbide (B4C) possesses unique physical and thermal properties. In this paper, B4C based composites toughened by TiB2 were fabricated by in-situ reaction sintering with the original microcrystalline powders B4C, TiO2 and glucose. The influences of sintering temperature and content of TiO2 on the sintering behavior and mechanical properties were investigated. (TiB2, Al2O3)/B4C and (TiB2,SiC)/B4C composites with almost fully dense were fabricated by using additives of Al2O3 and Si powders and sintering at 1950°C and 1900°C, the fracture toughness of composites reach to 7.09 and 6.35 MPa•m1/2 respectively. The analysis of microstructure shows that the main toughen mechanism is the crack deflection due to the existence of residual stress.

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Luo, H. H., D. Z. Wang, H. X. Peng, Cheng Liu, and C. K. Yao. "The Formation Process of the Microstructure of Al2O3-Al3Ti-Al In-Situ Composite." Microscopy and Microanalysis 3, S2 (August 1997): 727–28. http://dx.doi.org/10.1017/s1431927600010527.

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In the last decade, new in-situ processing techniques, such as DIMOX™, XD™, VLS and SHS, for fabricating metal and intermetallic matrix composites have emerged. It is expected that the in-situ formed composites may reveal not only excellent dispersion of fine reinforcing particles, but high thermodynamical stability and high temperature performance. The fully dense Al2O3-Al3Ti-57Vol%Al composite was in-situ processed by combing combustion synthesis with squeeze casting utilizing the reaction between TiO2 powder (with average diameter of 0.6μm and volume fraction of 14%) and pure Al (99.5%). First, the 14Vol%TiO2/Al bulk materials were fabricated via squeeze casting method, subsequently, the TiO2/Al materials were heat treated to form final in-situ composites. Using XRD, SEM, TEM and HRTEM techniques, the microstructure and its evolution were investigated.The X-ray diffraction pattern of the composite is shown in Fig.1 which indicates that the composite is composed of A12O3, Al3Ti and Al. According to the reaction formula between TiO2 and Al the volume fraction of Al in the composite is about 57%. Fig.2 is a typical scanning electron micrograph of the composite.

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Journal articles on the topic 'TI02 COMPOSITE'

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