Journal articles: 'In situ ceramic composite'

1

Zhang, Guo Jun, Hideki Kita, Naoki Kondo, and Tatsuki Ohji. "Strengthening Effect of In-Situ Dispersed Hexagonal Boron Nitride in Ceramic Composites." Key Engineering Materials 317-318 (August 2006): 163–66. http://dx.doi.org/10.4028/www.scientific.net/kem.317-318.163.

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High strength particulate ceramic composites are in general reinforced by strong dispersoids, such as strong ceramic particles (SiC, TiB2, ZrO2, et al) and strong metallic particles (Mo, W, et al). In this work high strength ceramic composites with in-situ synthesized hexagonal boron nitride (h-BN) have been prepared and characterized. As an example, we manufactured mullite-BN composites by reactive hot pressing (RHP) using aluminum borates (9Al2O3·2B2O3 and 2Al2O3·B2O3) and silicon nitride as starting materials. The obtained material RHPed at 1800°C showed a strength of 540 MPa, which was 1.64 times higher than that of the monolithic mullite ceramics. TEM observation revealed that the composite had an isotropic microstructure with a fine mullite matrix grain size of less than 1 μm and a nano-sized h-BN platelets of about 200 nm in length and 60∼80 nm in thickness. The high strength was suggested to be from the reduced matrix grain size and the small toughening effect by the h-BN platelets. In addition, this kind of ceramic composite demonstrates low Young’s modulus that is beneficial to the thermal/mechanical shock resistance, and excellent machinability.

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Zhao, Zhong Min, Long Zhang, Hong Bai Bai, Jian Zheng, Jian Jiang Wang, and Y. Fu. "Fabrication of Nano-Micron Al₂O₃-ZrO₂ Ceramic Eutectic Composites from the Melts by the SHS Metallurgical Process." Key Engineering Materials 280-283 (February 2007): 1053–56. http://dx.doi.org/10.4028/www.scientific.net/kem.280-283.1053.

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New nano-submicron textured Al2O3-ZrO2 ceramic eutectic composites were obtained from high-temperature melts produced by the SHS metallurgical process with intro-granular and 1-3 composite structures. Nano-micron textured ceramic composites were naturally self-assembled in one quick step by the SHS metallurgical process, in-situ synthesis and symbotic eutectic transformation under high degree of undercooling. The experimental results indicated that the Al2O3-ZrO2 ceramic eutectic composites with ZrO2 fibers at the nano-submicron scale are only suitable for the ceramic composite with hypoeutectic composition under the conditions of the experiment.

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Liu, Bing Qiang, Chuan Zhen Huang, Han Lian Liu, and Xue Wen Chong. "Development of Whisker Toughening Ceramic Cutting Tool Composite by In Situ Synthesis Technology." Key Engineering Materials 431-432 (March 2010): 201–4. http://dx.doi.org/10.4028/www.scientific.net/kem.431-432.201.

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While whisker toughening ceramic cutting tool composites have excellent mechanical properties at either room or high temperature, the development of them is often limited by some difficulties in the fabrication and application. Here a TiC whisker toughening Al2O3 ceramic cutting tool composite is developed by in situ synthesis technology. Experimental results show the flexure strength, fracture toughness and Vickers hardness of the composite can achieve to 855.7MPa, 7.63 MPa•m1/2 and 19.5GPa, respectively. Being different to that of conventional whisker toughening ceramic composites, the toughness of the composite is dominated by the chemical interface bonding between TiC and Al2O3, which increases with increasing sintering temperature, and the sliding resistance is suggested to be due to the physical absorption and mechanical meshing between the two debonded surfaces.

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Ramírez, Cristina, Pilar Miranzo, Maria Isabel Osendi, and Manuel Belmonte. "In Situ Graded Ceramic/Reduced Graphene Oxide Composites Manufactured by Spark Plasma Sintering." Ceramics 4, no. 1 (December 29, 2020): 12–19. http://dx.doi.org/10.3390/ceramics4010002.

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The present work merges two key strategies for the manufacturing of advanced ceramics, in particular, the development of functionally graded materials (FGMs) and the addition of graphene-based fillers into a ceramic matrix. A silicon nitride/reduced graphene oxide FGM composite is produced, in one step, from a single powder composition using the spark plasma sintering (SPS) technique with an asymmetric setting of the punches and die to create a continuous temperature gradient along the cross section of the powder compact. A deep microstructural and mechanical characterization has been done across the specimen thickness. The FGM composite exhibits bottom-top gradients in both the matrix grain size (150% increase) and α-phase content (89→1%). The FGM bottom surface is 10% harder than the top one and, on the other hand, the latter is 15% tougher. The presence of reduced graphene oxide sheets homogeneously distributed within the ceramic composite reduces the mechanical gradients compared to the monolithic silicon nitride FGM, although allows reaching a maximum long-crack toughness value of 9.4 MPa·m1/2. In addition, these graphene-based fillers turn the insulating ceramics into an electrical conductor material.

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Liao, Zhongquan, Yvonne Standke, Jürgen Gluch, Katalin Balázsi, Onkar Pathak, Sören Höhn, Mathias Herrmann, et al. "Microstructure and Fracture Mechanism Investigation of Porous Silicon Nitride–Zirconia–Graphene Composite Using Multi-Scale and In-Situ Microscopy." Nanomaterials 11, no. 2 (January 22, 2021): 285. http://dx.doi.org/10.3390/nano11020285.

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Silicon nitride–zirconia–graphene composites with high graphene content (5 wt.% and 30 wt.%) were sintered by gas pressure sintering (GPS). The effect of the multilayer graphene (MLG) content on microstructure and fracture mechanism is investigated by multi-scale and in-situ microscopy. Multi-scale microscopy confirms that the phases disperse evenly in the microstructure without obvious agglomeration. The MLG flakes well dispersed between ceramic matrix grains slow down the phase transformation from α to β-Si3N4, subsequent needle-like growth of β-Si3N4 rods and the densification due to the reduction in sintering additives particularly in the case with 30 wt.% MLG. The size distribution of Si3N4 phase shifts towards a larger size range with the increase in graphene content from 5 to 30 wt.%, while a higher graphene content (30 wt.%) hinders the growth of the ZrO2 phase. The composite with 30 wt.% MLG has a porosity of 47%, the one with 5 wt.% exhibits a porosity of approximately 30%. Both Si3N4/MLG composites show potential resistance to contact or indentation damage. Crack initiation and propagation, densification of the porous microstructure, and shift of ceramic phases are observed using in-situ transmission electron microscopy. The crack propagates through the ceramic/MLG interface and through both the ceramic and the non-ceramic components in the composite with low graphene content. However, the crack prefers to bypass ceramic phases in the composite with 30 wt.% MLG.

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Wang, Ying Chun, Jian Guo Li, and Yaohe Zhou. "Research on the In Situ Fabrication of Bioceramic Composite Coatings by Laser Cladding." Key Engineering Materials 330-332 (February 2007): 625–28. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.625.

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Hydroxyapatite(HAP) has excellent osteoconductive properties. By controlling the Ca/P ratio better biphasic calcium phosphate ceramics can be produced than pure HAP ceramics. β- calcium pyrophosphate(β-Ca2P2O7) is a new biodegradable ceramic material and its biological response is quite similar to HAP. Obtaining HAP and other bioactive calcium phosphate ceramic coatings has been a popular research field in the past. In our research a new bioceramic composite coating was obtained by laser cladding with pre-depositing mixed powders of CaHPO4·2H2O and CaCO3 directly on the metal substrate. Its main constituents are HAP and β-Ca2P2O7. The microstructure of the coating consists of minute granular HAP that is distributed among the overlapped club-shaped or needle-like β-Ca2P2O7. The hardness distribution in the cladding layer is even and its value is much higher than that in the substrate. There is a bonded structure of the epitaxial planar growth between the substrate and cladding layer, and both a typical cellular microstructure in the middle and an equiaxed microstructure at the top of the cladding layer.

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7

Riedel, Ralf. "Novel Method Produces Dense In Situ Ceramic Composite." Materials and Processing Report 3, no. 9 (December 1988): 2–3. http://dx.doi.org/10.1080/08871949.1988.11752214.

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Ehrenfried, Lisa M., David Farrar, David Morsley, and Ruth Cameron. "Mechanical Behaviour of Interpenetrating Co-Continuous β-TCP-PDLLA Composites." Key Engineering Materials 361-363 (November 2007): 407–10. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.407.

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Co-continuous degradable polymer-ceramic composites were produced via in-situ polymerization of (D,L-lactic)acid monomer within a porous β-tricalcium phosphate matrix. The mechanical properties of both the composite and the unfilled porous ceramic were investigated with compressive testing. The average stress to failure increased from 1.3±0.1 MPa for the unfilled ceramic matrix to 82±2 MPa for the composite. The Young’s modulus increased from approximately 20 MPa to 700±42 MPa. A combination of X-ray micro-tomography and mechanical testing provided insight into the failure mechanisms of the composite. Stress may be deflected by crack bridging around the polymer phase leading to debonding of the polymer along the crack lines.

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9

Huang, Kai Jin. "Synthesis of Al₂O₃/AlB₁₂/Al Composite Ceramic Powders by Pulsed Nd:YAG Laser Igniting Method and a Study of their Mechanical Properties." Applied Mechanics and Materials 26-28 (June 2010): 919–24. http://dx.doi.org/10.4028/www.scientific.net/amm.26-28.919.

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Based on the combined toughening principle, pure Al2O3/AlB12/Al composite ceramic powders have been synthesized using pulsed Nd:YAG laser igniting method. This method starts from Al and B2O3 powder mixtures, after which Al2O3/AlB12/AlN composite ceramics were fabricated by hot-press sintering at 1600°C for 2h under the protection of a N2 atmosphere. XRD and SEM techniques were used to characterize the phases and morphologies of the powders and the ceramics. The bending strength and the fracture toughness of the ceramics were measured by the three-point bending method and the indentation fracture method, respectively. The results show that the pure Al2O3/AlB12/Al composite ceramic powders can be successfully synthesized by pulsed Nd:YAG laser igniting method because the adiabatic temperature of Al-B2O3 system is more than 1800K. Al2O3 and AlB12 phases were formed by the liquid-liquid reaction mechanism and the liquid-solid reaction mechanism, respectively. The bending strength and the fracture toughness of the Al2O3/AlB12/AlN composite ceramics were 525.86MPa and 5.68MPa.m1/2, respectively. These values are 50.25% and 42% greater than those of the pure Al2O3 ceramic (350MPa and 4MPa.m1/2) due to the reinforcing and toughening in-situ formation of small AlN particles.

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Huang, Kai Jin, Li Yan, Hua Min Kou, and Chang Sheng Xie. "Synthesis of Al₂O₃/AlB₁₂/Al Composite Ceramic Powders by a New Laser-Induction Complex Heating Method and a Study of their Mechanical Properties." Applied Mechanics and Materials 29-32 (August 2010): 596–601. http://dx.doi.org/10.4028/www.scientific.net/amm.29-32.596.

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Based on the combined toughening principle, pure Al2O3/AlB12/Al composite ceramic powders have been synthesized using a new laser-induction complex heating method. This method starts from Al and B2O3 powder mixtures, after which Al2O3/AlB12/AlN composite ceramics were fabricated by hot-press sintering at 1600°C for 2h under the protection of a N2 atmosphere. XRD and SEM techniques were used to characterize the phases and morphologies of the powders and the ceramics. The bending strength and the fracture toughness of the ceramics were measured by the three-point bending method and the indentation fracture method, respectively. The results show that the pure Al2O3/AlB12/Al composite ceramic powders can be successfully synthesized by this new laser-induction complex heating method because the adiabatic temperature of Al-B2O3 system is more than 1800K. Al2O3 and AlB12 phases were formed by the liquid-liquid reaction mechanism and the liquid-solid reaction mechanism, respectively. The bending strength and the fracture toughness of the Al2O3/AlB12/AlN composite ceramics were 551.44MPa and 6.04MPa.m1/2, respectively. These values are 57.55% and 51% greater than those of the pure Al2O3 ceramic (350MPa and 4MPa.m1/2) due to the reinforcing and toughening in-situ formation of small AlN particles.

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Wang, Weizhan, Taiyong Zhao, Fangao Meng, Peng Tian, Guanglei Li, and Zhigang Chen. "Study of Impact Characteristics of ZrO2 Ceramic Composite Projectiles on Ceramic Composite Armor." Materials 15, no. 4 (February 17, 2022): 1519. http://dx.doi.org/10.3390/ma15041519.

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Exploring new armor-piercing materials is crucial for improving the penetrative ability of projectiles. Based on the process of in situ solidification injection molding through ceramic dispersant hydrolytic degradation, a ZrO2 ceramic material suitable for use as the tip of a 12.7 mm kinetic energy (KE) projectile was prepared. The ZrO2 ceramic tip can be matched with the metal core of a conventional projectile to form a ceramic composite projectile, increasing the damage to the Al2O3 ceramic composite armor. Specifically, the ZrO2 ceramic tip can increase the impact load on the Al2O3 ceramic panel, prolonging the pre-damage phase and reducing the stable penetration phase, shortening the mass erosion time of the metal core compared with a 12.7 mm metal KE projectile tip. The ceramic composite projectile with the ZrO2 ceramic tip has a lower critical penetration velocity than a 12.7 mm metal KE projectile for Al2O3 ceramic composite armor. Furthermore, the residual velocity, residual length, and residual mass of the metal core of the ceramic composite projectile that penetrated the Al2O3 ceramic composite armor are greater than those of a 12.7 mm metal KE projectile.

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Zhang, Jun, Hai Jun Su, Lin Liu, and Heng Zhi Fu. "Laser Zone-Remelted Alumina-Based Eutectic In Situ Composite." Materials Science Forum 539-543 (March 2007): 832–36. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.832.

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Due to excellent oxidation and corrosion resistance at elevated temperature, oxide ceramic could be the preference served at high temperature oxidizing atmosphere over a long period of time. In recent years, alumina-based eutectic in situ composite prepared by various solidification techniques, which has superior properties even close to the melting point about 2100K, has been paid much attention. In this paper, Al2O3/YAG/ZrO2 ternary eutectic and hypoeutectic ceramics are prepared from melt by laser zone-remelting technique, the rapid solidification characteristic and the mechanical property of the composites are investigated. The results show that: (1) Compared to sintered composite with the same composition, laser zone-remelted Al2O3/YAG/ZrO2 eutectic in situ composite has different microstructure showing fine interpenetrated network with Al2O3, YAG and ZrO2 phases continuously intergrown, while none of pores, grain boundaries and amorphous phases is found. (2) The scanning rate and the power density of the laser beam has strong effect on the microstructure morphology. When the power density is determined, the eutectic spacing is reduced with the scanning rate increased. The characteristic eutectic spacings and phase sizes of YAG and Al2O3 are about 2~3μm, and the characteristic dimension of ZrO2 is less than 1μm. (3) The hardness and the room-temperature fracture toughness of Al2O3/YAG/ZrO2 eutectic are respectively Hv=16.7±2.0 GPa and KIC=8.0±2.0 MPa.m1/2, and those of hypoeutectic are respectively Hv=15.8±2.0 GPa and KIC=3.9±1.0 MPa.m1/2.

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Su, Hai Jun, Jun Zhang, Sha Jiao, Lin Liu, and Heng Zhi Fu. "Fabrication and Characterization of Al₂O₃/GdAlO₃ Eutectic Ceramic In Situ Composite by Laser Zone Remelting." Advanced Materials Research 160-162 (November 2010): 773–76. http://dx.doi.org/10.4028/www.scientific.net/amr.160-162.773.

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In situ composite of Al2O3/GdAlO3(GAP) ceramic eutectic prepared by directional solidification is an interesting candidate for the manufacture of turbine blades because of its excellent mechanical properties. In the present paper, directionally solidified Al2O3/GAP eutectic in situ composite ceramics are manufactured by the laser zone remelting technique to investigate the rapid solidification process. The laser power and scanning rate necessary to carry out the ceramic melt growth is determined. The characteristic microstructure is investigated by scanning electron microscopy (SEM), energy disperse spectroscopy (EDS) and X-ray diffraction (XRD). The as-solidified Al2O3/GAP eutectic presents an elongated colony structure consisting of only -Al2O3 and GAP phases with an oriented growth array. The eutectic spacing is strongly dependent on the laser scanning rate, rapidly decreasing to the sub-micron range for the samples grown at the highest rate. Besides, the formation condition and evolution of the particular microstructure of the composite during rapid solidification are discussed.

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Ma, Feng Cang, Ping Liu, Wei Li, Xin Kuan Liu, Xiao Hong Chen, and Di Zhang. "Mechanical Properties and Strengthening Mechanisms of In Situ (TiB+TiC)/Ti-1100 Composite at Elevated Temperature." Materials Science Forum 686 (June 2011): 727–32. http://dx.doi.org/10.4028/www.scientific.net/msf.686.727.

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In this paper, Ti-1100 composites reinforced with TiB+TiC ceramic particles were fabricated using in situ technologies. Mechanical properties of the composites with different volume fractions of TiB and TiC reinforcements were evaluated by tensile tests at 873K. The breakage of TiB was observed during the failure process of the composite. Strengthening efficiencies of the reinforcements for different composites were calculated. The strengthening mechanisms in this composite during tensile tests were discussed. It was suggested that the effect of the solution of C, which was produced in the preparation process, also can not be ignored for such a composite.

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Zhang, Kun, Wang Fen, Jianfeng Zhu, and Huae Wu. "Mechanical properties and microstructure of Al2O3/TiAl in situ composites doped with Cr and V2O5." Science of Sintering 44, no. 1 (2012): 73–80. http://dx.doi.org/10.2298/sos1201073z.

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Al2O3/TiAl in situ composites doped with Cr and V2O5 were successfully prepared from Ti, Al, TiO2, Cr and V2O5 by hot pressing. The effect of in situ formed Al2O3 content on the phase composition, microstructure and mechanical properties of Al2O3/TiAl composites were investigated. The results show that the as-synthesized composites mainly consisted of ?-TiAl/?2-Ti3Al matrix and dispersive Al2O3 reinforcing phases. The in situ formed fine Al2O3 ceramic particles mainly disperse on the grain boundaries of TiAl, resulting in refinement of TiAl matrix, which improves the mechanical properties of the Al2O3/TiAl in situ composite. The composite with 7.54 at.% Al2O3 possesses the maximum flexural strength and fracture toughness of 335.38 MPa and 5.39 MPa m1/2, respectively. The strengthening mechanism was also discussed in detail.

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Kalemtas, A., Gürsoy Arslan, and Ferhat Kara. "Pressureless Melt Infiltrated Non-Oxide Ceramic-Metal Composites." Key Engineering Materials 403 (December 2008): 251–52. http://dx.doi.org/10.4028/www.scientific.net/kem.403.251.

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In the present study highly dense (open porosity < 1 %), light-weight (d £ 2.85 g/cm3) and Al4C3-free non-oxide ceramic-metal composites were produced at comparatively low temperatures ( 1250°C) by pressurless melt infiltration. Phase analysis of the SiC-B4C-Al composites revealed that a significant amount of hygroscopic Al4SiC4 and Al4C3 phases were formed. Si3N4 powder was added in different amounts to the SiC-B4C powder batches to suppress formation of these phases via in-situ reactions during the infiltration process. X-ray diffraction results of the SiC-B4C-Si3N4-Al composites confirmed that the incorporation of Si3N4 to the SiC-B4C system reduced or eliminated the formation of the hygroscopic phases and resulted in in-situ formation of AlN, SiC and Si phases in the composite.

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Li, Jilin, Yunhua Xu, and Wanying Li. "Interface Calculation of In Situ Micro-Nano TaC/NbC Ceramic Particle Composites." Materials 16, no. 5 (February 24, 2023): 1887. http://dx.doi.org/10.3390/ma16051887.

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Traditional experiments are difficult to accurately and quantitatively measure the interfacial properties of composites, such as interfacial bonding strength, interfacial microelectronic structure, and other information. It is particularly necessary to carry out theoretical research for guiding the interface regulation of Fe/MCs composites. In this research, the first-principles calculation method is used to systematically study the interface bonding work; however, in order to simplify the first-principle calculation of the model, dislocation is not considered in this paper, including interface bonding characteristics and electronic properties of α-Fe- and NaCl-type transition metal carbides (Niobium Carbide (NbC) and Tantalum Carbide (TaC)). The interface energy is related to the bond energy between the interface Fe atoms, C atoms and metal M atoms, and the interface energy Fe/TaC < Fe/NbC. The bonding strength of the composite interface system is accurately measured, and the interface strengthening mechanism is analyzed from the perspectives of atomic bonding and electronic structure, which provides a scientific guiding ideology for regulating the interface structure of composite materials.

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Amosov, A. P., Yu V. Titova, G. S. Belova, D. A. Maidan, and A. F. Minekhanova. "SHS of highly dispersed powder compositions of nitrides with silicon carbide Review." Izvestiya vuzov. Poroshkovaya metallurgiya i funktsional’nye pokrytiya, no. 4 (December 10, 2022): 34–57. http://dx.doi.org/10.17073/1997-308x-2022-4-34-57.

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The application of the process of self-propagating high-temperature synthesis (SHS) to prepare highly dispersed powder nitride-carbide compositions from the most common refractory nitride (Si3N4, AlN, TiN) and carbide (SiC) compounds with a particle size of less than 1 μm is considered. The advantages of composite ceramics over single-phase ceramic materials and such trends of its development as the transition to nanostructured ceramics and the application of in situ processes of direct chemical synthesis of nanoparticles of components in the composite body are described. The attractiveness of the SHS process as one of the promising in situ processes characterized by simplicity and cost-effectiveness, the possibility of obtaining highly dispersed ceramic powders by burning mixtures of inexpensive reagents is shown. Considerable attention is paid to the consideration of the results of the application of azide SHS, based on the use of sodium azide and gasified halide salts as part of mixtures of initial powders of nitrided and carbidized elements during their combustion in nitrogen gas. The review of publications devoted to the application of SHS to obtain highly dispersed composite powders Si3N4–SiC, AlN–SiC and TiN–SiC, promising for use in sintering of the corresponding composite ceramic materials of submicron and nano-sized structure with improved properties, lower brittleness, good machinability, lower sintering temperatures compared with single-phase ceramic materials made of nitrides or carbides as well as for other applications, is presented. The results of the application of azide SHS are presented in detail both in the form of the results of thermodynamic calculations and the results of experimental research of combustion parameters, combustion product structure and composition. The advantages and disadvantages of using the combustion process for the synthesis of nitride compositions with silicon carbide, the causes of the disadvantages and the directions of further research to eliminate them are discussed.

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Yu, Jing Jing, Shu Suo Li, and Ya Fang Han. "Study on Interface Reactions between Nb-Si System In Situ Composite and Ceramics." Materials Science Forum 546-549 (May 2007): 1495–500. http://dx.doi.org/10.4028/www.scientific.net/msf.546-549.1495.

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A Nb-Si system in-situ composite Nb-16Si-24Ti-6Cr-6Al-2Hf(at%) was fabricated using vacuum arc melting method, and then was metallurgically reacted with four kinds of ceramics ZrO2, Y2O3 stabilized ZrO2, Y2O3, SiC+Si3N4 at elevated temperature. The microstructures in the interface reaction zones were investigated by SEM and EDS. The results showed that different extent chemical reactions between the composite and these four kinds of ceramics took place. It has been found that HfO2 riched layer formed near the interfaces between the Nb-Si in-situ composite and three ceramics of ZrO2, Y2O3 stabilized ZrO2 and Y2O3, and thickness of the reaction zones were about 100μm, 10μm, 1μm respectively. C and N elements in SiC+Si3N4 ceramic diffused to the composite at elevated temperature, and a new phase that rich of Ti, C and N elements appeared nearby the interface and accumulated inhomogenously. It may be concluded that the interface reactions of both ZrO2 and SiC+Si3N4 with Nb-Si composite were very violent, therefore they are not suitable as face-coat materials of shell molds for investment casting; the interface reaction of Y2O3 stabilized ZrO2 and Nb-Si composite was slighter than ZrO2 and SiC+Si3N4, and it can be used as face-coat material of shell molds, the interface reaction of Y2O3 and Nb-Si composite was very slight, and is recommended as an ideal face-coat materials of shell molds.

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Jin, Qi, Xue Ping Ren, Hong Liang Hou, Yan Ling Zhang, and Hai Tao Qu. "In Situ Synthesis and Structural Design of Ti/TiC Functionally Graded Materials." Materials Science Forum 913 (February 2018): 515–21. http://dx.doi.org/10.4028/www.scientific.net/msf.913.515.

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In this paper, the metal/ceramic functionally graded composites are prepared. The thermal stress of TiC/Ti functionally graded composites are simulated by Abaqus finite element analysis software to study the influence of the number of layers, the gradient layer thickness and the gradient of distribution index.The optimal structural parameters of the TiC/Ti functional gradient composites are obtained as the number of layers of 6 and the gradient distribution index 0.8. According to the optimized structural parameters, Ti and C powders are mixed by high-energy ball milling, then the TiC/Ti functional gradient composites are prepared by spark plasma sintering. The gradient distribution of composition and microstructure in TiC/Ti functionally graded composites are achieved, which can solve the problem of mismatch for the physical properties between the metal and the ceramic in the composite material.

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NAM, KI WOO. "CRACK-HEALING BEHAVIOR AND BENDING STRENGTH OF Al2O3/SiC COMPOSITE CERAMICS ACCORDING TO THE AMOUNT OF ADDITIVE Y2O3." International Journal of Modern Physics B 24, no. 15n16 (June 30, 2010): 2910–15. http://dx.doi.org/10.1142/s0217979210065842.

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Three Al 2 O 3/ SiC composite ceramics were prepared, which included 1, 3 or 5 wt. % Y 2 O 3, and their high-temperature bending strengths and in-situ crack-healing behaviors examined. A surface elliptical-crack of about 100 µm in diameter was introduces on the specimens using a Vickers hardness indenter. From in-situ observations, the Al 2 O 3/ SiC composite ceramic with 3 wt.% Y 2 O 3 showed superior crack-healing ability than the 1 and 5 wt.% Y 2 O 3 ceramics. The as-cracked specimen with 3 wt.% Y 2 O 3 showed strength recovery on healing for 1 hr at 1473 K in air, which may have been due to the lower crack-healing temperature on the addition of 3 wt.% Y 2 O 3. The heat-resistance limit temperatures of the crack-healed Al 2 O 3/ SiC composite ceramics were 1073, 1373 and 873 K for 1, 3 and 5 wt.% Y 2 O 3, respectively.

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Juhani, Kristjan, Jakob Kübarsepp, Marek Tarraste, Jüri Pirso, and Mart Viljus. "Microstructure Formation and Performance of Reactive Sintered Titanium Oxycarbide Base Ceramic-Ceramic Composites." Key Engineering Materials 799 (April 2019): 131–35. http://dx.doi.org/10.4028/www.scientific.net/kem.799.131.

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Reactive sintering is a process where synthesis reaction of the ceramic phases is combined with sintering (densification) of the composite. Dense lightweight titanium oxycarbide-aluminium oxide ceramic-ceramic composites were produced from titanium dioxide, carbon black as graphite source and aluminium precursors by high energy attritor milling, followed by reactive sintering. Titanium oxycarbide and aluminium oxide phases were synthesized during reactive sintering in situ. To investigate the microstructure evolution and phase formation, the specimens were sintered at different temperatures (600-1725 °C) in vacuum. Scanning electron microscopy and X-ray diffraction were used to analyze the microstructure and phase formation. Mechanical performance (hardness and fracture toughness) was evaluated.

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Li, Wei. "Study on Interface Structure and In Situ Formation Mechanism in Laser Surface Ceramic Process." Advanced Materials Research 538-541 (June 2012): 1847–51. http://dx.doi.org/10.4028/www.scientific.net/amr.538-541.1847.

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Laser ceramic modification technology is an effective way to improve the surface performance of titanium alloy. This paper summarized the in situ formation mechanism of ceramic phases and the interface structure between ceramic phases and the matrix during the laser ceramic process on the surface of titanium alloy. The future research area was also indicated that theoretical study on composite ceramic coating preparation should be strengthened by combining the laser alloying and in situ formation technology on the surface of titanium alloy.

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Savchenko, Nickolai, Irina Sevostyanova, Mikhail Grigoriev, Tatiana Sablina, Ales Buyakov, Maxim Rudmin, Andrey Vorontsov, Evgeny Moskvichev, Valery Rubtsov, and Sergei Tarasov. "Self-Lubricating Effect of WC/Y–TZP–Al2O3 Hybrid Ceramic–Matrix Composites with Dispersed Hadfield Steel Particles during High-Speed Sliding against an HSS Disk." Lubricants 10, no. 7 (July 4, 2022): 140. http://dx.doi.org/10.3390/lubricants10070140.

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WC/Y–TZP–Al2O3 hybrid ceramic–matrix composites (CMCs) with dispersed Hadfield steel particles were sintered and then tested at sliding speeds in the range of 7–37 m/s and contact pressure 5 MPa. Fast and low-temperature sinter-forging allowed obtaining micron-sized WC grains, submicron-sized alumina-reinforced yttria partially stabilized polycrystalline tetragonal zirconia (Y–TZP–Al2O3), and evenly distributed Hadfield steel grains. Such a microstructure provided new hybrid characteristics combining high hardness with high fracture toughness and tribological adaptation. The CMCs demonstrated low friction and high wear resistance that were better than those demonstrated by other composite materials such as, for example, MAX-phase composites, zirconia-base ceramics, ZrB2-SiC ceramics, and metal matrix WC–(Fe–Mn–C) composites. These good tribological characteristics were obtained due to the in situ mechanochemical formation of iron tungstates FeWO4 and Fe2WO6 on the worn surfaces of composite samples. These mixed oxides were included in multilayer subsurface structures that provided the self-lubricating and self-healing effects in high-speed sliding because of their easy shear and quasi-viscous behavior.

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25

Golyshev, A., and A. Malikov. "Microstructure and mechanical properties of multilayer (TiB+TiB2+TiC)/Ti-6Al-4V composite in laser powder bed fusion additive manufacturing process." Journal of Physics: Conference Series 2131, no. 4 (December 1, 2021): 042013. http://dx.doi.org/10.1088/1742-6596/2131/4/042013.

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Abstract The paper presents the analysis of the physical and mechanical properties of the heterogeneous material based on the ceramics TiB, TiB2, TiC, B4C and metal alloy Ti-6Al-4V formed by the SLM method. The effect of ceramic particles TiB, TiB2, TiC, B4C resulting from in situ synthesis under the laser action on the microstructure and hardness of the formed metal-matrix composite has been studied. Under discussion are the main mechanisms of change of the microstructure with secondary ceramic insertions, the hardness is measured at the micro-level.

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26

Zhai, Chuan Xin, Yan Li, Xin Yang Wang, Liu Jie Xu, and Shi Zhong Wei. "Fabrication of Fe-Based Al₂O₃-TiC Ceramic /Steel Composite by Self-Propagation High-Temperature Synthesis." Advanced Materials Research 105-106 (April 2010): 495–98. http://dx.doi.org/10.4028/www.scientific.net/amr.105-106.495.

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The Fe-Based Al2O3-TiC Ceramic Composite was fabricated by combining the methods of Self-propagating High-temperature Synthesis with casting. The microstructures of ceramic layer and interface were characterized via SEM, EDS and X-ray diffraction. The Results show that the microstructure of ceramic layer is dense, and the in-situ Al2O3 and TiC particles with size of 1-2 μm are distributed on the ferrite matrix. The hardness of compact ceramic layer reaches 48HRC, and it has graded distribution from ceramic layer to the ferrite matrix. The composite interface between ceramic and matrix is compact, and takes on flexuous. The composite material bonds in a metallographic manner, with high bonding strength.

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27

Yang, Rui, Kuiwu Li, Likui Yin, Kai Ren, Yu Cheng, Taotao Li, Jianping Fu, Taiyong Zhao, Zhigang Chen, and Jinlong Yang. "Study on the Penetration Power of ZrO2 Toughened Al2O3 Ceramic Composite Projectile into Ceramic Composite Armor." Materials 15, no. 8 (April 15, 2022): 2909. http://dx.doi.org/10.3390/ma15082909.

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This work aims to improve the penetration ability of a 14.5 mm standard armor-piercing projectile into ceramic/armor steel (Al2O3/RHA) composite armor. To this end, ZrO2 toughened Al2O3(ZTA) is prepared as the material for bullet tips, utilizing in situ solidification injection molding that is realized via ceramic dispersant hydrolytic degradation. The penetration power of ZTA ceramic composite projectile, compared with standard armor, against 15 mm armor steel (RHA) and 30 mm Al2O3/RHA composite armor, is studied by ballistics testing combined with numerical simulation. The Tate theory is optimized and then employed to calculate the penetration depth and bullet core’s residual mass when ZTA ceramic composite projectile penetrates into Al2O3/RHA composite armor. The results show that when penetrating RHA of 15 mm, the penetration area of ZTA ceramic composite projectile into RHA increases by 27.59% and the exit area by 42.93%. While the standard projectile fails to penetrate the 30 mm Al2O3/RHA composite armor, the ZTA ceramic composite armor-piercing projectile succeeds, with the mass loss reduced by 66.67% over the standard one. The ZTA ceramic composite bullet has a better performance than the standard bullet in penetrating RHA and Al2O3/RHA composite armors. The test results, simulation, and theoretical analysis are consistent. This study has practical values for engineering applications to design new ceramic composite bullets.

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HIRAI, Toshio, Makoto SASAKI, and Masayuki NIINO. "CVD in-situ ceramic composites." Journal of the Society of Materials Science, Japan 36, no. 410 (1987): 1205–11. http://dx.doi.org/10.2472/jsms.36.1205.

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29

Liu, Zhao Wei, Xiao Wang, Yu Lin Qiao, and Si Jie Wang. "Structure and Properties of Ti-Si Composite Ceramic Coatings by Laser Cracking with SiO<sub>2</sub> Particles." Key Engineering Materials 915 (March 29, 2022): 53–58. http://dx.doi.org/10.4028/p-di5401.

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Ti-Si composite ceramic coating containing SiO2 particles was prepared on 45 steel substrate by in-situ laser pyrolysis with laser power of 600W and laser wavelength of 980nm. The density and wear resistance of the composite ceramic coating were improved. By means of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), reciprocating friction and wear tester, the element composition, existing forms, surface morphology and friction and wear properties of Ti-Si composite ceramic coatings with different mass fraction of SiO2 particles were analyzed. The results show that the addition of SiO2 particles can improve the surface density and inorganic degree of the composite ceramic coating. When the mass fraction of SiO2 is 1% and the load is 1N, the friction coefficient of the composite ceramic coating is 61% lower than that of 45 steel. When the mass fraction of SiO2 is 5% and the load is 3N, the friction coefficient of the composite ceramic coating is 51% lower than that of 45 steel. The composite ceramic coatings show good antifriction performance and wear resistance.

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30

Yu, Y. D., I. L. Tangen, M. A. Einarsrud, R. Høier, T. Grande, and J. K. Solberg. "Microstructures in Pressureless Sintered AIN-SiC Ceramics." Microscopy and Microanalysis 7, S2 (August 2001): 1124–25. http://dx.doi.org/10.1017/s143192760003169x.

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Aluminum nitride (AlN) is known to have a high thermal conductivity and is one of the valid candidates as substrate material for integrated circuits. The material also has a potential in metal production and handling. However, AlN has only a moderate flexural strength and fracture toughness. It has been reported that SiCA1N composites (SiC/AIN ratio ≥ 50%) can be manufactured by means of pressureless sintering. Furthermore, it is possible to fabricate self-reinforced SiC-based materials with whisker-like crystals in composite ceramics by choosing appropriate sintering additive and condition. in the present study, we investigated the possibility to prepare in-situ formed SiC-whisker reinforced AlN-materials and studied the microstructure of the composite.An AlN-SiC composite ceramic sample (20 vol% SiC) was prepared for the investigation. The AlN-SiC composite was processed from a mixture of the starting powders with 2.5 wt% Al2O3-Y2O3 as a sintering additive.

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31

Janó, Viktória. "Study on the Production of Metal Matrix Composite Layer by Laser Melt Injection Technology." Materials Science Forum 537-538 (February 2007): 177–84. http://dx.doi.org/10.4028/www.scientific.net/msf.537-538.177.

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In-situ synthesized Al2O3 reinforced metal-ceramic composite coating was fabricated on lowalloyed carbon steel surface by laser cladding. Injection of the ceramic powder into the melted surface can be difficult due to the effect of surface tension and to the lower density of the Al2O3 particles, compared to that of the steel matrix. These difficulties can be avoided by the in-situ synthesis of Al2O3 particles in the liquid steel matrix. In this paper, the results of experiments performed by laser beam will be introduced, together with the interpretation of these results. Experiments proved that the Al2O3 ceramic phase can be created in-situ in the steel matrix.

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32

Janó, Viktória. "Ceramic Reinforced Metal Matrix Nano and Micro-Composite Layers Produced by Combined Laser Melt Injection Technology and Thermochemical Surface Treatment." Materials Science Forum 812 (February 2015): 77–82. http://dx.doi.org/10.4028/www.scientific.net/msf.812.77.

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In-situ synthesized Nb (C,N) reinforced metal-ceramic composite layers were fabricated on nitridable (16MnCr5) and non-nitridable (S235J) steel surface by combined laser melt injection technology and ferritic nitrocarburizing treatment. The feasibility of processing composites layer by an in situ reaction using laser beam were carried out. Beside that the hardness of the treated layers increases up to 1000-1170 HV0.5 in the diffusion zone and after it the hardness of the samples reach 300-450 HV0.5, which is related the Nb alloying depth (1200-1400 μm). The results of the composite layer are presented in this paper.

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33

AYDIN, Gulsum, Kenan YILDIRIM, and Ayse KALEMTAS. "Naturally Derived a-Tricalcium Phosphate Based Porous Composite Bead Production." Material Science Research India 16, no. 3 (December 18, 2019): 240–51. http://dx.doi.org/10.13005/msri/160307.

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In this study, a simple, innovative approach is applied to produce porous a-TCP-CeO2-Al2O3 composite beads via using bovine bone-derived hydroxyapatite, cerium oxide, and alumina ceramics. Bovine-bone derived hydroxyapatite was obtained via calcination of bones at 950°C for 3 hours. Hydroxyapatite is a thermally unstable biomaterial at high temperatures, and depending on its stoichiometry decomposes at 800-1200°C. Sodium alginate was successfully used as an in situ gelling templates for the production of the ceramic beads and starch, an environmentally friendly and economic pore-forming agent, is used to achieve interconnected, highly open porosity containing composite beads. Sintering of the ceramic−starch−alginate green composite beads at 1200°C for 1 hour resulted in the decomposition of the hydroxyapatite phase and formation of a-TCP. XRD analysis revealed that a-TCP-CeO2-Al2O3 composite beads were achieved. XRD analysis confirmed the formation of a-TCP phase in all composite compositions. SEM investigations of the produced composite beads revealed that bimodal pore size distribution, fine and coarse, was achieved.

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34

Chen, Xiao Hu, Xiao Min Chen, Huang Zhao, and Ji Huai Wu. "In Situ Synthesis of Rod-Like Tielite / Alumina Ceramic Composites via Mechanical Activation." Key Engineering Materials 352 (August 2007): 111–14. http://dx.doi.org/10.4028/www.scientific.net/kem.352.111.

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The purpose of this paper is to investigate the possibility of rod-like Al2TiO5 / α-Al2O3 composites in situ formation via a mechanical activation process. A QM-ISP-4 Planetary Mill was employed to activate mechanically the mixtures of anatase and corundum in air at room temperature for different times. The milled powder mixtures were pressed into platelets and then sintered in air at 1300°C for 3 h. The XRD results showed that only Al2TiO5 and α-Al2O3 phases could be detected in the sintered samples when the activated time reached 30 hours. The SEM observations illustrated the unusual microstructure of Al2TiO5 / α-Al2O3 ceramic composite materials. Abnormal grains with longitudinal length ~10 μm23 transversal length ~1 μm and equiaxed matrix grains of ~3 μm on an average were observed. EDXA proved that the rod-like grains and the fine equiaxed matrix grains were composed of Al2TiO5 and α-Al2O3, separately. The roles of anisotropic grain growth caused by mechanical activation are discussed for the in situ formation of rod-like Al2TiO5 / α-Al2O3 ceramic composite materials.

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35

Zhang, You Feng, and Jun Li. "Microstructure and Wear Resistance of the Composite Coatings Fabricated on Titanium Alloys by Laser Cladding." Advanced Materials Research 139-141 (October 2010): 398–401. http://dx.doi.org/10.4028/www.scientific.net/amr.139-141.398.

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In situ reaction synthesized TiB reinforced titanium matrix composites were fabricated using rapid non-equilibrium synthesis techniques of laser cladding. TiB/Ti composite coating was treated on Ti-6Al-4V surface using Ti and B powder mixture by laser cladding. Microstructure and dry sliding wear behavior of the in situ synthesized TiB/Ti composite coatings were investigated by optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), energy-dispersive spectroscopy (EDS), hardness tester and friction and wear tester. The composite coatings consist of Ti, TiB and intermetallic compounds. The TiB reinforcement dispersed homogeneously in the composite coatings. The wear tests show that the friction coefficient and wear weight loss ratio of the coatings is lower than that of the Ti-6Al-4V alloy. The composite coating was reinforced by the in situ synthesized TiB ceramic particles. Based on the SEM observation, effects of scan speed on hardness and wear resistance of the laser cladding coatings were investigated and discussed.

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36

Roy, Siddhartha, Jan Frohnheiser, and Alexander Wanner. "Effect of ceramic preform freeze-casting temperature and melt infiltration technique on the mechanical properties of a lamellar metal/ceramic composite." Journal of Composite Materials 54, no. 15 (November 26, 2019): 2001–11. http://dx.doi.org/10.1177/0021998319890661.

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Elastic properties, compressive stress–strain behaviour and progressive damage evolution of poly-domain metal/ceramic composite samples fabricated by infiltration of Al12Si melt in freeze-cast alumina preforms are studied. Two different preform freezing temperatures were employed to vary the lamellae size while infiltration was carried out using two different techniques – squeeze-casting and die-casting. Due to the faster cooling kinetics at the lower freezing temperature, the lamellae size in the composites based on these preforms are finer and this results into higher compressive strength and stiffness of this composite along the freezing direction. Among the two techniques employed for melt infiltration, the very fast rate of pressure application in die-casting distorts the lamellar structure of the ceramic along the freezing direction. As a result, in die-cast composite samples, the strength and stiffness along the freezing direction are reduced significantly in comparison to the samples infiltrated by squeeze-casting. In-situ scanning electron microscopy under external compression was used to study the progressive damage mechanism in one poly-domain composite sample infiltrated by squeeze-casting. Transverse cracking of the high-angle ceramic lamellae is identified as the predominant damage mechanism.

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37

Yang, Thomas C. K., and Dabir S. Viswanath. "In-Situ Measurement of Emissivities of Ceramic-Polymer Composite Materials." Journal of the American Ceramic Society 80, no. 1 (January 1997): 157–64. http://dx.doi.org/10.1111/j.1151-2916.1997.tb02804.x.

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38

Cui, Chun Xiang, Yan Chun Li, Tie Bao Wang, Shuang Jin Liu, and Suek Bong Kang. "NbC and VC Nanoparticles Reinforced Fe-Si-Mn Matrix Composite In Situ Synthesized by Plasma Jet." Advanced Materials Research 415-417 (December 2011): 71–75. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.71.

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In situ NbC and VC nanoparticles reinforced Fe-Si-Mn-Nb-V matrix composite was carried out using a plasma jet with a plasma gas flow of (Ar + CH4) for very short time. The process involve improving the efficiency of the reaction in terms of consumption of the available active nitrogen atoms as well as the production of very fine and homogeneous distribution of all reinforcing phases of ceramic particles, preferable in the nanometer range. The nanoreinforcements synthesized by in situ reaction in this hybrid composite are NbC and VC ceramic particles.

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39

Wang, Shaopeng, Lian Zhou, Changjiu Li, Zhengxian Li, Hongzhan Li, and Lijing Yang. "Micrographic Properties of Composite Coatings Prepared on TA2 Substrate by Hot-Dipping in Al–Si Alloy and Using Micro-Arc Oxidation Technologies (MAO)." Coatings 10, no. 4 (April 10, 2020): 374. http://dx.doi.org/10.3390/coatings10040374.

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A composite coating composed of intermetallic compounds, Al–Si alloys, and an oxide ceramic layer was prepared on TA2 substrate by hot-dipping Al–Si alloy and micro-arc oxidation (MAO) methods. The microstructure and composition distribution of the resulting hot-dipped Al–Si alloy layer and MAO-caused ceramic layer were studied by scanning electron microscope (SEM) and energy dispersive spectrum (EDS). In addition, the phase composition of the diffusion layer obtained by the Al–Si alloy hot-dipping procedure was investigated by electron backscattered diffraction (EBSD), and the phase structure of the MAO-treated layer was studied by X-ray diffraction (XRD) analysis and X-ray photoelectron spectroscopy (XPS). The MAO method can make the hot-dipped Al–Si alloy layer in-situ oxidized to form a ceramic layer. Finally, a three-layer composite coating composed of a diffusion layer formed by the Ti–Al–Si interdiffusion, an Al–Si alloy layer and a ceramic layer was prepared on TA2 substrate. Compared with TA2 substrate, the TA2 sample with a three-layer composite coating has larger friction coefficient and less abrasion loss. The three-layer composite coating can significantly improve the wear resistance of TA2. A technical composite method was developed to the low cost in-situ growth of alumina-based ceramic wear-resistant coatings on TA2 substrate.

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40

Popov, Oleksii, Dmitry V. Shtansky, Vladimir Vishnyakov, Oleksandra Klepko, Sergey Polishchuk, Magzhan K. Kutzhanov, Elizaveta S. Permyakova, and Petro Teselko. "Reaction Sintering of Machinable TiB2-BN-C Ceramics with In-Situ Formed h-BN Nanostructure." Nanomaterials 12, no. 8 (April 18, 2022): 1379. http://dx.doi.org/10.3390/nano12081379.

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Soft TiB2-BN-C hetero-modulus ceramics were sintered with the assistance of in-situ reactions during the hot pressing of TiN-B4C precursors. TiB2 formation was observed already after the hot pressing at 1100 °C, remaining the only phase identifiable by XRD even after sintering at 1500 °C. Analysis of reaction kinetics allows us to assume that the most probable reaction controlling stage is boron atoms sublimation and gas phase transfer from B4C to TiN. Reactive sintering route allows almost full densification of TiB2-BN-C composite ceramics at 1900 °C. The processes enable the formation of multilayer h-BN nanosheets inside the TiB2 matrix. The manufactured TiB2-33BN-13C ceramic with K1C = 5.3 MPa·m1/2 and HV = 1.6 GPa is extremely thermal shock-resistant at least up to quenching temperature differential of 800 °C. The sintered UHTC composite can be machined into complex geometry components.

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41

Zhai, Ping, Xiao Feng Duan, Da Qian Chen, Chong Hai Wang, Fang Gao, and Bo Dong. "Carbon Fiber Reinforced Phosphate Porous Ceramic Composites." Key Engineering Materials 512-515 (June 2012): 916–19. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.916.

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Fiber porous ceramics are the excellent candidates for a variety of applications, and thus, their research is a hotspot in recent years. In this study, carbon fiber reinforced phosphate porous ceramics composites were prepared by acupuncture and in-situ solidification vacuum-assisted liquid-phase infiltration method. The tensile strength of composite was tested by universal testing machine, the microstructures of the specimen were observed by scanning electron microscopy while the thermal analysis was detected by Thermo Gravimetric Analyzer. The results show that the carbon fiber reinforced phosphate porous ceramics composites which is prepared by the technology showed above have a pore rate of 63.7%.The tensile strength reached 50.2MPa with an average pore size of at most 50μm.It also has good thermal shock resistance.

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42

Lv, Xiangzhe, Zaiji Zhan, and Haiyao Cao. "Microstructure Evolution and Mechanical Properties of Needle-like ZrB2 Reinforced Cu Composites Manufactured by Laser Direct Energy Deposition." Micromachines 13, no. 2 (January 28, 2022): 212. http://dx.doi.org/10.3390/mi13020212.

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Laser additive manufacturing is an advanced material preparation technology, which has been widely used to prepare various materials, such as polymers, metals, ceramics and composites. Zirconium diboride (ZrB2) reinforced copper composite material was fabricated using laser direct energy deposition technology. The microstructure and phase composition of the composite material were analyzed, and the influence of laser energy density on the microstructure and mechanical properties of composite materials was discussed. The results showed that the needle-like ZrB2 ceramic reinforcement was successfully synthesized via an in-situ synthesis reaction. The composites were mainly composed of needle-like ZrB2, Ni dendrites and a Cu matrix. The morphological changes of Ni dendrites could be observed at the interface inside the composite material: cellular crystals → large-sized columnar dendrites → small-sized dendrites (along the solidification direction). The continuous Ni dendritic network connected the ZrB2 reinforcements together, which significantly improved the mechanical properties of the composite material. At a laser energy density of 0.20 kJ/mm2, the average microhardness of the composite material reached 294 HV0.2 and the highest tensile strength was 535 MPa. With the laser energy density increased to 0.27 kJ/mm2, the hardness and tensile strength decreased and the elongation of the Cu composites increased due to an increase in the size of the ZrB2 and a decrease in the continuity of the Ni dendritic.

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43

Ai, Yun Long, Kai Wu, Xiang Hua Xie, Bing Liang Liang, Wen He, and Wei Hua Chen. "Effects of Nb₂O₅/La₂O₃ Synergistic Modification on Phase Composition, Microstructure and Mechanical Properties of Al₂O₃ Ceramics Prepared by Microwave Sintering." Key Engineering Materials 633 (November 2014): 49–52. http://dx.doi.org/10.4028/www.scientific.net/kem.633.49.

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Nb2O5-7.5La2O3-Al2O3 composite ceramics were prepared by microwave sintering. The influence of Nb2O5 and La2O3 proportion on the microstructure and mechanical properties of Al2O3 ceramics was investigated. The results show that when the Nb2O5 content was lower than La2O3, the columnar LaAl11O18 grains were generated by the reaction of La2O3 with Al2O3. When the Nb2O5 content was higher than La2O3, the surplus Nb2O5 induced the formation of columnar Al2O3 grains. The growth of columnar Al2O3 grains were promoted synergistically by LaNbO4 formed in-situ and Nb2O5. The 5Nb2O5-7.5La2O3-Al2O3 composite ceramic exhibited excellent comprehensive properties: ρr=99.3% (relative density), HV=11.2GPa (microhardness), KIC= 6.4MPa·m1/2 (fracture toughness), σ=304.3MPa (bending strength).

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44

Jiang, Gaoqiang, Chengyun Cui, Lu Chen, Yucheng Wu, and Xigui Cui. "In Situ Synthesis of (M:Nb,Ta)C/Ni35 Composite Coating Cladded on 40Cr Steel." Materials 14, no. 23 (December 3, 2021): 7437. http://dx.doi.org/10.3390/ma14237437.

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To improve the wear and corrosion resistance of the pump barrel material (40Cr steel), a (M:Nb,Ta)C/Ni35 composite cladding coating by in situ synthesis of composite carbides was conducted. The effects of ceramic micro-particles content on the phase composition, microstructure of the coating, structural characteristics of (M:Nb,Ta)C and the tribology and electrochemical corrosion behavior were systematically studied. The increase of ceramic micro-particles changed the morphology of (M:Nb,Ta)C with the size from sub-micron to micron. The (M:Nb,Ta)C dispersed along the grain boundary inhibits the growth of the grains. During friction, the spherical structure exhibited a rolling lubrication effect and the petal structure provided a stronger attachment ability to resist the shear. The corrosion occurred at the grains, exhibiting corrosion pits, in which the high content ceramic micro-particles were relatively shallow. Moreover, a few dot corrosion pits were distributed along the grain boundaries without (M:Nb,Ta)C. Therefore, to improve the corrosion resistance, a thin composite carbide coating with good wear and corrosion resistance was prepared.

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45

Lee, Joon Hyun, and Jeong Guk Kim. "Thermographic Damage Detection of Ceramic Matrix Composites During Tension Testing." Key Engineering Materials 321-323 (October 2006): 825–30. http://dx.doi.org/10.4028/www.scientific.net/kem.321-323.825.

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The fracture behavior of Nicalon fiber reinforced calcium aluminosilicate (CAS) glass-ceramic matrix composites (Nicalon/CAS) was investigated with the aid of a nondestructive evaluation (NDE) technique. Infrared (IR) thermography was employed for unidirectional Nicalon/CAS composite specimens. During tensile testing, an IR camera was used for in-situ monitoring of progressive damages of Nicalon/CAS samples. The IR camera provided the temperature changes during tensile testing. Microstructural characterization using scanning electron microscopy (SEM) was performed to investigate the fracture mechanisms of Nicalon/CAS composites. In this investigation, the thermographic NDE technique was used to facilitate a better understanding of the fracture mechanisms of the Nicalon/CAS composites during tensile testing.

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46

Yang, Jin Shan, Shao Ming Dong, Ping He, Qing Gang Li, Bin Wu, Jian Bao Hu, and Zhi Hui Hu. "Fabrication and Properties of C_f/Ti₃SiC₂-SiC Composites Using Ti₃SiC₂as Inert Filler." Key Engineering Materials 512-515 (June 2012): 681–84. http://dx.doi.org/10.4028/www.scientific.net/kem.512-515.681.

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Because of its combined characteristics of metals and ceramics, such as low density, high Young’s modulus, thermal and chemical resistance with low hardness, high electrical and thermal conductivity, it was expected that the introduction of Ti3SiC2 to fiber reinforced ceramic matrix can make the composite own some unique properties. In the present research, Ti3SiC2 powders used as inert fillers were fabricated by the in-situ reaction between Ti and polycarbosilane mixtures. The purity of Ti3SiC2 powders analyzed by XRD was determined by RIR method, which is a semi-quantitative XRD analysis. The results showed that the purity of Ti3SiC2 powders is about 96%. Cf/Ti3SiC 2-SiC composites are obtained by polymer infiltration and pyrolysis process using Ti3SiC2 powders as the inert fillers. The bending strength of Cf/Ti3SiC2-SiC composites was about 160 MPa.

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47

Jiao, Yuhong, Jianfeng Zhu, Xuelin Li, Chunjie Shi, Bo Lu, Fen Wang, and Waras Abdul. "Mechanical Properties of Al Matrix Composite Enhanced by In Situ Formed SiC, MgAl2O4, and MgO via Casting Process." Materials 14, no. 7 (April 2, 2021): 1767. http://dx.doi.org/10.3390/ma14071767.

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Al matrix composite, reinforced with the in situ synthesized 3C–SiC, MgAl2O4, and MgO grains, was produced via the casting process using phenolic resin pyrolysis products in flash mode. The contents and microstructure of the composites’ fracture characteristics were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mechanical properties were tested by universal testing machine. Owing to the strong propulsion formed in turbulent flow in the pyrolysis process, nano-ceramic grains were formed in the resin pyrolysis process and simultaneously were homogeneously scattered in the alloy matrix. Thermodynamic calculation supported that the gas products, as carbon and oxygen sources, had a different chemical activity on in situ growth. In addition, ceramic (3C–SiC, MgAl2O4, and MgO) grains have discrepant contents. Resin pyrolysis in the molten alloy decreased oxide slag but increased pores in the alloy matrix. Tensile strength (142.6 ± 3.5 MPa) had no change due to the cooperative action of increased pores and fine grains; the bending and compression strength was increasing under increased contents of ceramic grains; the maximum bending strength was 378.2 MPa in 1.5% resin-added samples; and the maximum compression strength was 299.4 MPa. Lath-shaped Si was the primary effect factor of mechanical properties. The failure mechanism was controlled by transcrystalline rupture mechanism. We explain that the effects of the ceramic grains formed in the hot process at the condition of the resin exist in mold or other accessory materials. Meanwhile, a novel ceramic-reinforced Al matrix was provided. The organic gas was an excellent source of carbon, nitrogen, and oxygen to in situ ceramic grains in Al alloy.

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Mehra, Deepak, Manas Mohan Mahapatra, and Suraj Prakash Harsha. "Effect of wear parameters on dry abrasive wear of RZ5-TiC in situ composite." Industrial Lubrication and Tribology 70, no. 2 (March 12, 2018): 256–63. http://dx.doi.org/10.1108/ilt-12-2016-0306.

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Purpose The purpose of this study is to increase the wear resistance of Mg alloy by adding hard ceramic particles to it. The inclusion of hard ceramic particles further strengthen the Mg alloy, resulting in higher wear resistance. Mg alloys containing Zn, rare earth and Zr exhibit high specific strength and excellent creep resistance, making them suitable for aerospace components such as aircraft gearboxes and generator housings. Design/methodology/approach In the present study, composites have been produced in situ by using RZ5 mg alloy as matrix and TiC as reinforcement by self-propagating high-temperature synthesis technique. The abrasive wear behavior of RZ5 Mg alloy matrix reinforced with TiC particulates has also been examined. The pin-on-disc apparatus has been used for the tests. The abrasive paper is used as a counter body, and the results are obtained by changing sliding distance and applied load. Findings A notable enhancement in the wear resistance and mechanical properties of tested composite has been observed as compared to the RZ5 Mg alloy as a matrix. There is a uniform increment in the change in weight loss of RZ5-TiC composite with increasing sliding distance and applied load, but it decreases with increasing TiC content. The coefficient of friction (µ) also decreases uniformly with an increase in the reinforcement of TiC, but it decreases with an increase in applied load and sliding distance. The investigation of the worn composite, which determines dominant wear mechanisms as abrasion and plowing grooves on tested samples, has been done using field emission scanning electron microscopy. Originality/value The current manuscript provides a detailed abrasive wear analysis of RZ5-TiC composite by using different wear parameters. Specifically, extensive experimental data have been provided for RZ5-TiC composite. The effects of parameters such as applied load, sliding distance and Wt.% of TiC on the weight loss and coefficient of friction of the composites have been analyzed and discussed thoroughly.

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Jin, B. S., Y. F. Jiao, and G. Li. "Preparation of TiC/ Fe Surface Composite by a Casting–SHS Process." Key Engineering Materials 373-374 (March 2008): 666–69. http://dx.doi.org/10.4028/www.scientific.net/kem.373-374.666.

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Steel castings with a ceramic reinforced surface layer have been prepared by a casting process combined with self-propagation high-temperature synthesis (SHS). Two material systems, Fe-Ti-C-Al and Al-Fe2O3, were selected in this paper to prepare the steel castings with a ceramic reinforced surface layer. During the process, high temperature steel melt was poured into a sand mould in which SHS performs were cast. The performs were ignited by the high temperature steel melt. As a result, an SHS reaction happened and ceramic reinforcements were synthesized inside the mould. After the penetration of the molten steel and the scattering of the ceramic reinforcement, a steel casting with an in-situ ceramic reinforced surface layer was obtained.

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Shi, Qiang, Han Lian Liu, Chuan Zhen Huang, and Bin Zou. "Study on the In Situ Fabricated Titanium Nitride-Based Ceramic Cutting Tool Materials Reinforced by Titanium Diboride." Advanced Materials Research 500 (April 2012): 679–84. http://dx.doi.org/10.4028/www.scientific.net/amr.500.679.

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The titanium diboride reinforced titanium nitride-based ceramic cutting tool composite materials were fabricated by a new technology namely in situ synthesis followed by hot-pressed sintering. The experimental results showed that the highest density and the best mechanical properties of the composite material were obtained when the content of Ni was 5wt%. X-ray diffraction (XRD) was used to identify the phases of the composite. Microstructures of the composite were observed by means of scanning electron microscope (SEM). It is concluded that the sintered material was pure, no harmful reaction products was found; with the increase of Ni content, the proportion of short rod-like TiB2 increased, fracture toughness of the composite materials were improved because lots of TiB2 were pulled out; bridging phenomenon of short rod-like particles and metal particles were observed in the crack propagating process. The main toughening mechanisms of the composites were deflection and bridging of the crack as well as grains pulling out.

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Journal articles on the topic 'In situ ceramic composite'

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