Journal articles: 'Method of etching in the presence of metals'

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Pashangeh, Shima, Seyyed Sadegh Ghasemi Banadkouki, Fatemeh Besharati, Fatemeh Mehrabi, Mahesh Somani, and Jukka Kömi. "Color Light Metallography Versus Electron Microscopy for Detecting and Estimating Various Phases in a High-Strength Multiphase Steel." Metals 11, no. 6 (May 23, 2021): 855. http://dx.doi.org/10.3390/met11060855.

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In this study, fresh attempts have been made to identify and estimate the phase constituents of a high-silicon, medium carbon multiphase steel (DIN 1.5025 grade) subjected to austenitization at 900 °C for 5 min, followed by quenching and low-temperature bainitizing (Q&B) at 350 °C for 200 s. Several techniques were employed using different chemical etching reagents either individually (single-step) or in combination of two or more etchants in succession (multiple-step) for conducting color metallography. The results showed that the complex multiphase microstructures comprising a fine mixture of bainite, martensite and retained austenite phase constituents were selectivity stained/tinted with good contrasting resolution, as observed via conventional light optical microscopy observations. While the carbon-enriched martensite-retained austenite (M/RA) islands were revealed as cream-colored areas by using a double-step etching technique comprising etching with 10% ammonium persulfate followed by etching with Marble’s reagent, the dark gray-colored bainite packets were easily distinguishable from the brown-colored martensite regions. However, the high-carbon martensite and retained austenite in M/RA islands could be differentiated only after resorting to a triple-step etching technique comprising etching in succession with 2% nital, 10% ammonium persulfate solution and then warm Marble’s reagent at 30 °C. This revealed orange-colored martensite in contrast to cream-colored retained austenite in M/RA constituents, besides the presence of brown-colored martensite laths in the dark gray-colored bainitic matrix. A quadruple-step technique involving successive etching with 2% nital, 10% ammonium persulfate solution, Marble’s reagent and finally Klemm’s Ι reagent at 40 °C revealed even better contrast in comparison to the triple-step etching technique, particularly in distinguishing the RA from martensite. Observations using advanced techniques like field emission scanning electron microscopy (FE-SEM) and electron back scatter diffraction (EBSD) failed to differentiate untempered, high-carbon martensite from retained austenite in the M/RA islands and martensite laths from bainitic matrix, respectively. Transmission electron microscopy (TEM) studies successfully distinguished the RA from high-carbon martensite, as noticed in M/RA islands. The volume fraction of retained austenite estimated by EBSD, XRD and a point counting method on color micrographs of quadruple-step etched samples showed good agreement.

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Llorca-Isern, Núria, Ana Maria Escobar, and Oriol Rius. "Scalable Methods to Obtain Superhydrophobicity onto Metallic Surface." Materials Science Forum 879 (November 2016): 2501–6. http://dx.doi.org/10.4028/www.scientific.net/msf.879.2501.

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Superhydrophobic surfaces, with extremely high water contact angles (CAs) of more than 150° are of special interest due to their various anti-adhesive and self-cleaning properties. Recent studies demonstrate that the superhydrophobicity principally results from the presence of binary structures at both the micrometre and nanometre scales together with the low-energy wax-like materials on the surfaces. Materials with similar properties, to those of the lotus leaf structure are very useful in several areas, such as the aeronautical industry and civil engineering; so many methods have been developed to mimic the lotus leaf structure. Metals are very important and irreplaceable engineered materials in many industrial fields. An alternative method for enhancing superhydrophobicity on different metals is proposed. The method proceeds by coating the metallic surface with a superhydrophobic reactive such as dodecanoic acid being a common application its use in paints with eco-friendly properties. The goal of this study is to induce direct superhydrophobicity by a single step and coating process on prepared surfaces of pure commercial aluminium 99.9 wt %, pure commercial 99.9 wt % copper and stainless steel grade 316L (UNS S31603). The chemical reaction proceeds by etching the activated surface with lauric acid in ethanol solutions.

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Abdulkadir, Auwal, Nur Afidah Md. Noor, Azlan Abdul Aziz, and Mohd Zamir Pakhuruddin. "Broadband Anti-Reflection in Black Silicon Fabricated by Two-Step Silver-Assisted Wet Chemical Etching for Photovoltaics." Solid State Phenomena 301 (March 2020): 167–74. http://dx.doi.org/10.4028/www.scientific.net/ssp.301.167.

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This paper reports broadband anti-reflection in black silicon (b-Si) fabricated by two-step metal-assisted chemical etching (MACE) for potential photovoltaic (PV) applications. The method involves deposition of silver nanoparticles (Ag NPs) in aqueous solution of HF:AgNO3, followed by etching in HF:H2O2:DI H2O solution for different duration (10-25 s). Effects of etching time towards surface morphological and optical properties of b-Si nanowires are investigated. Surface morphological characterization confirms presence of b-Si nanowires with heights of 350-570 nm and diameter of 150-300 nm. The b-Si nanowires exhibit outstanding broadband anti-reflection due to refractive index grading effect. This is represented as weighted average reflection (WAR) in the 300-1100 nm wavelength region. After 20 s of etching, b-Si nanowires with height of 570 nm and width of about 200 nm are produced. The nanowires demonstrate WAR of 5.5%, which represents the lowest WAR in this investigation. This results in absorption of 95.6% at wavelength of 600 nm. The enhanced broadband light absorption yields maximum potential short-circuit current density (Jsc(max)) of up to 39.7 mA/cm2, or 51% enhancement compared to c-Si reference. This facile b-Si fabrication method for broadband enhanced anti-reflection could be a promising technique to produce potential PV devices with high photocurrent.

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Adibah, Nurulain A., S. N. Azella, and M. F. Abd Shukur. "Synthesis of Ti₃C₂ Mxene through In Situ HF and Direct HF Etching Procedures as Electrolyte Fillers in Dye-Sensitized Solar Cell." Materials Science Forum 1023 (March 2021): 15–20. http://dx.doi.org/10.4028/www.scientific.net/msf.1023.15.

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MXene is the new family of two-dimensional (2D) transition metal carbides, carbonitrides and nitrides discovered in 2011. The unique properties of 2D MXene such as excellent mechanical properties, hydrophilic surfaces and metallic conductivity made it interesting for application in electrodes of rechargeable batteries, supercapacitors, photocatalysts, catalysts, transparent conducting films, and flexible high-strength composites. The MXene can be synthesized through a selective etching process by using either in-situ HF (hydrofluoric acid) or direct HF methods. This study reports on the effect of the in-situ HF and direct HF etching procedures on the morphology of the synthesis Ti2C3 MXene using titanium aluminum carbide (Ti2AlC3) as precursor. The morphology and elements presence were evaluated by using variable pressure field emission scanning electron microscope (FESEM) and energy dispersion X-ray (EDX) spectroscopy analyses, respectively. The analysis shows that the MXene synthesized through the direct HF method was successfully delaminated compared to the in-situ HF procedures.

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Frolov, Ivan N., Sergey L. Zabudkov, Andrey V. Yakovlev, and Marina I. Lopukhova. "SELECTION OF MODE OF ANODIC TREATMENT OF GRAPHITE IN A SPENT NITRIC ACID ETCHING SOLUTION FOR PRODUCING THERMALLY EXPANDING GRAPHITE COMPOUNDS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENII KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 62, no. 6 (July 8, 2019): 77–83. http://dx.doi.org/10.6060/ivkkt.20196206.5873.

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The possibility of using galvanic waste for the synthesis of graphite thermo expanded compounds has been shown. An electrolyte on the basis of a spent nitrate solution of etching copper parts containing cations of various metals in its composition was taken as an example, thereby solving an environmental issue related to the problem of utilization of solutions containing nitric or sulfuric anions in its composition. The processes occurring in the synthesis of thermally expanding graphite compounds on platinum and graphite electrodes in the electrolyte under investigation were studied by the method of potentiodynamic curves. The currents on the potentiodynamic curves before reaching the oxygen evolution potential were due to the oxidation of the surface-functional groups followed by intercalation of the graphite matrix. It was revealed that the potential for oxygen evolution in the electrolyte based on the spent nitric acid solution of etching of copper parts is slightly lower than in 58% HNO3 due to the presence of metal cations in the composition. Free metal cations attract a part of water molecules to form hydrate shells, while copper cations form complexes where H2O molecules are ligands, which makes it difficult to release oxygen. In the electrochemical synthesis of thermally expanding graphite compounds, potentiostatic and galvanostatic modes were applied. A range of potentials of 1.8 - 2.2 V was chosen for performing the synthesis in the potentiostatic mode. Recommendations are given for the application of the galvanostatic mode with the current of anodic treatment of 60 - 140 mA (per 1 g of graphite) for the synthesis of graphite thermo expanding compounds in industrial volumes. The thermo expanded graphite obtained in this manner is characterized by a bulk density of less than 2 g/dm3.

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Pustovoit, V. N., and Yu V. Dolgachev. "REVISITING THE NATURE OF SITES OF MARTENSITE NUCLEATION DURING STEEL HARDENING." Izvestiya. Ferrous Metallurgy 62, no. 2 (March 30, 2019): 109–14. http://dx.doi.org/10.17073/0368-0797-2019-2-109-114.

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Presence of microvolumes most prepared for the martensite emergence in austenite is discussed. Aming many works dealing with martensitic transformations, rare works are devoted to the location of martensite origin. This aspect of transformation is important, since it allows us to obtain new knowledge about scenarios for γ → α transformation development during quenching of steel. The martensite embryos are submicron austenite volumes that are most prepared for phase transition and are characterized by increased energy. Experimental results were obtained by the methods of high-temperature metallography. Steel structure observed as a result of vacuum etching was studied, as well as the surface relief caused by shear during the martensitic transformation. The resulting structural patterns made it possible to observe most of the possible places for martensite emergence: nonmetallic inclusions, twins, high-angle and small-angle grain boundaries, previously formed martensite crystals, dislocations and elements of the disclination structure. It is shown that a high dislocation density is observed in the twin area, which facilitates nucleation of martensite as a result of disappearance of part of elastic energy of the dislocation when atoms inside the embryo are rearranged. When nucleation occurs on the grain boundaries, energy is released, which is used to construct a new interphase boundary and to compensate emerging elastic energy. The relative energy of the boundaries of different types was estimated by the method of multi-beam interferometry. The depth of the grooves that were formed on the surface by thermal etching was measured. Elements of disclination structure resulting from inhomogeneous deformation were observed, which are also sites of germinal centers formation. It is noted that nanoareas with ferromagnetic order, which are present in paramagnetic austenite, may not be observed with the help of the technique used in this work. However, magnetism plays a decisive role in realization of one or another scenario of the development of phase transformation in steels. Obtaining data on the interaction of ferromagnetic areas in austenite with each other, with crystal lattice defects, the magnetic field, and data on their lifetime, number and size is an important task for future research.

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Ovchinnikov, Victor, and Andriy Shevchenko. "Self-Organization-Based Fabrication of Stable Noble-Metal Nanostructures on Large-Area Dielectric Substrates." Journal of Chemistry 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/158431.

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A cost-effective fabrication of random noble-metal nanostructures with a feature size of the order of 10 nm on a large-area dielectric substrate is described. The method combines dry etching of the substrate through a self-organized metal mask with a directional deposition of a multilayered metal film. The technique allows one to create metal nanoislands on a nanopatterned dielectric template with an enhanced adhesion between the metal and the dielectric. The use of the adhesion layer—that makes the structures stable—is important in view of variety of optical and other potential applications of the structures. We observe that the presence of the adhesion sublayer dramatically influences both the morphological and optical properties of the structures. The results of this work can be of interest in regard to the development of new approaches to self-organization-based nanofabrication of extremely small metal and metal-dielectric nanostructures on large-area substrates.

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Cai, Yina, Binxue Ren, Chifang Peng, Cunzheng Zhang, and Xinlin Wei. "Highly Sensitive and Selective Fluorescence “Turn-On” Detection of Pb (II) Based on Fe3O4@Au–FITC Nanocomposite." Molecules 26, no. 11 (May 26, 2021): 3180. http://dx.doi.org/10.3390/molecules26113180.

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New nanocomposites, Fe3O4@Au–FITC, were prepared and explored to develop a fluorescent detection of Pb2+. The Fe3O4@AuNPs–FITC nanocomposites could be etched by Pb2+ in the presence of Na2S2O3, leading to fluorescence recovery of FITC quenched by Fe3O4@Au nanocomposites. With the increase of Pb2+ concentration, the fluorescence recovery of Fe3O4@AuNPs–FITC increased gradually. Under optimized conditions, a detection limit of 5.2 nmol/L of Pb2+ with a linear range of 0.02–2.0 µmol/L were obtained. The assay demonstrated negligible response to common metal ions. Recoveries of 98.2–106.4% were obtained when this fluorescent method was applied in detecting Pb2+ spiked in a lake-water sample. The above results demonstrated the high potential of ion-induced nanomaterial etching in developing robust fluorescent assays.

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Lutsik, Vladimir I., Yury V. Chursanov, and Anatoly V. Starovoytov. "INFLUENCE OF FORMATION OF THE COMPLEXES WITH DIFFERENT KIND OF LIGANDS ON KINETICS OF OXIDATIVE DISSOLUTION OF METALS." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, no. 8 (August 21, 2018): 22. http://dx.doi.org/10.6060/ivkkt20186108.5690.

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Rotating disk method has been used to study the dissolution of gold in the presence of an oxidizer and a mixture of dissimilar ligandforming reagents. Kinetic regularities of gold dissolution were investigated in aqueous systems thiourea-thiocyanate with Fe (III) and Cu (II) ions as the oxidizer; thiosulfate-thiocyanatewithFe(III)EDTA oxidizing complex and thiosulfate-thiocyanate with ammonia complex [Cu(NH3)4]2+ asoxidizing agent. Peculiarities of these mixed systems is a possibility to form the monoligandas as well as geteroligand complexes of gold. The influence of gold complexes formation with different sorts of ligands on the metal dissolution rate have been considered. The dependence of the dissolution rate on the ratio of ligands concentrations and on the oxidizing agent nature was investigated. Interrelation was established: the use of dissimilar ligandforming reagents - the higher thermodynamic stability of the geteroligand complexes of gold (relative to the homoligand ones) - synergistic increase of the gold dissolution rate. It was found that the heterophase reaction makromechanism for the thiourea-thiocyanate-Fe(III) system is determined by the proximity of the rates of chemical and diffusion stages (experimental activation energy - 21.6 kJ/mol; the reaction order in respect to the disk rotation frequency – 0.23). Diffusive limitation is due to the slow withdrawal of the reaction products -Au (I) compounds - from the solid phase surface. The formation of stronger heteroligand complexes and the corresponding increase in the reaction products concentration at the surface increases a rate of the metal diffusion into the solution. For the thiourea-thiosulfate-Fe(III)EDTA system a film formation of the reaction solid products on the gold surface was observed. To identify it the infrared reflection spectra of the polished gold surface after the etching were obtained. There is a strong absorption band on the spectra at 804 cm-1. Absorption in this area has been associated with the stretching vibrations of C=S bond of the thiourea molecules joined to the surface and the products of their oxidation.

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SKVORTSOV, Arkadiy A., Evgeniya O. GNATYUK, Margarita R. RYBAKOVA, and Ivan V. BURUKIN. "METHODS FOR HARDENING AND IMPROVEMENT OF FATIGUE CHARACTERISTICS OF TITANIUM AND IRON-CHROMIUM NICKEL ALLOY SAMPLES." Periódico Tchê Química 17, no. 35 (July 20, 2020): 425–36. http://dx.doi.org/10.52571/ptq.v17.n35.2020.37_skvortsov_pgs_425_436.pdf.

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This work describes the procedure for determining residual surface stresses using the mechanical method and four methods of hardening samples. The urgency of the problem stated in the article is due to the fact that surface tensile stresses arising in the manufacture of highly loaded parts can significantly reduce the mechanical, resource and fatigue characteristics of products. The aim of the study was to harden samples of titanium and iron-chromium-nickel alloys to improve their strength, fatigue and resource characteristics and determine residual stresses by layer-by-layer removal of the studied layers by electrochemical etching. The determination of surface residual stresses was carried out mechanically using a measuring and calculation complex during continuous etching of the metal from the test surface of the sample, which made it possible to measure the residual stresses at different depths and determine the energy of the surface stress state. Residual stresses were calculated from the deformation of the remaining part of the sample with a change in the depth of the studied layers. The hardening of the samples was carried out in four ways, namely: ultrasonic hardening; ultrasonic curing + Rosler (vibration processing); Rosler (vibration processing) + ultrasonic curing; Rosler (vibration processing) + ultrasonic hardening. The results of the study showed that the surface of the products is a weaker area than the inside. After quenching, surface compressive stresses arise for all samples of titanium and iron-chromium-nickel alloys. The preferred case of hardening is the second (ultrasonic hardening + centrifugal hardening). The presence of residual compressive stresses in the outer layers of the products increases their fatigue limit by ≈20%. The results of the work can be used to manufacture products with high mechanical, resource and fatigue characteristics.

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Mikhal’chenkov, Aleksandr, Sergey Fes’kov, Irina Kozarez, and Elena Slezko. "CHANGES IN THE MICROSTRUCTURE AND MICROHARDNESS OF 65G STEEL AFTER THERMAL HARDENING AND SURFACING WITH A LOW-CARBON ELECTRODE." Tekhnicheskiy servis mashin 1, no. 142 (January 2021): 107–14. http://dx.doi.org/10.22314/2618-8287-2020-59-1-107-114.

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When reinforcing the surfaces of the working bodies of tillage tools, they are surfaced with electrodes with a low-carbon rod. The surface in contact with the soil is not subjected to heat treatment. Recently, thermal hardening of local parts has been used. (Research purpose) The research purpose is in studying the transformation of the microstructure of 65G heat-strengthened steel deposited by an electrode with a low-carbon rod, as well as the specifics of the microhardness distribution in this section. (Materials and methods) Investigated in the cross-section of the structure of the deposited area by the standard method, consisting in the preparation of microsections, etching and directly microanalysis. (Results and discussion) The transformation of the microstructure of heat-strengthened steel 65G deposited by an electrode with a low-carbon rod is complex due to the specificity and versatility of the phase transformations that occur during its formation. The microhardness distribution plot in the cross-section of the surfacing area has a complex configuration, determined by the variety of structural components, the presence of deformation processes during crystallization and solidification, and the presence of preliminary thermal hardening of the base metal. (Conclusions) Increased values of the hardness of individual areas contribute to an increase in the abrasive wear resistance of the part. The presence of the fusion zone ensures the resistance of the deposited area to cracking. The zone of thermal influence has four clearly distinguishable areas: the drop in microhardness; the stable values according to the Vickers method; the near-shock zone; the fusion zone. The microhardness of the weld surface of the cushion is 410 Vickers or 42 Rockwell, which creates conditions for increasing the wear resistance of the surface friction. The use of electrodes with a low-carbon rod is advisable when conducting surfacing reinforcement of heat-strengthened steels.

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Mikhal’chenkov, Aleksandr M., Sergey A. Fes’kov, Irina V. Kozarez, and Elena I. Slezko. "CHANGES IN THE MICROSTRUCTURE AND MICROHARDNESS OF 65G STEEL AFTER THERMAL HARDENING AND SURFACING WITH A LOW-CARBON ELECTRODE." Tekhnicheskiy servis mashin 1, no. 142 (March 2021): 107–14. http://dx.doi.org/10.22314/2618-8287-2021-59-1-107-114.

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When reinforcing the surfaces of the working bodies of tillage tools, they are surfaced with electrodes with a low-carbon rod. The surface in contact with the soil is not subjected to heat treatment. Recently, thermal hardening of local parts has been used. (Research purpose) The research purpose is in studying the transformation of the microstructure of 65G heat-strengthened steel deposited by an electrode with a low-carbon rod, as well as the specifics of the microhardness distribution in this section. (Materials and methods) Investigated in the cross- section of the structure of the deposited area by the standard method, consisting in the preparation of microsections, etching and directly microanalysis. (Results and discussion) The transformation of the microstructure of heat-strengthened steel 65G deposited by an electrode with a low-carbon rod is complex due to the specificity and versatility of the phase transformations that occur during its formation. The microhardness distribution plot in the cross-section of the surfacing area has a complex configuration, determined by the variety of structural components, the presence of deformation processes during crystallization and solidification, and the presence of preliminary thermal hardening of the base metal. (Conclusions) Increased values of the hardness of individual areas contribute to an increase in the abrasive wear resistance of the part. The presence of the fusion zone ensures the resistance of the deposited area to cracking. The zone of thermal influence has four clearly distinguishable areas: the drop in microhardness; the stable values according to the Vickers method; the near-shock zone; the fusion zone. The microhardness of the weld surface of the cushion is 410 Vickers or 42 Rockwell, which creates conditions for increasing the wear resistance of the surface friction. The use of electrodes with a low-carbon rod is advisable when conducting surfacing reinforcement of heat-strengthened steels.

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Babachenko, A. I., H. A. Kononenko, Zh A. Dementieva, and R. V. Podolskyi. "Comparative researches of the quality indicators of the railway wheels of various methods of manufacture." Metallurgicheskaya i gornorudnaya promyshlennost, no. 1 (2019): 54–61. http://dx.doi.org/10.33101/s001-120019.

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Methodology. To identify the macrostructure of the metal of the wheels, deep hot etching was performed with a 50% aqueous hydrochloric acid solution according to GOST 10243. An assessment of the contamination of the metal of the wheels under study was performed in accordance with GOST 1778. The microstructure was detected by etching in 4% alcoholic nitric acid solution. Tensile tests of steel rims and wheel disks were carried out in accordance with GOST 1497, hardness according to GOST 9012, impact strength was determined according to GOST 9454. The results of mechanical tests were checked for compliance with the requirements of DSTU GOST 10791: 2016 Findings. The macro and microstructures of cast and solid-rolled railway wheels were studied. It was established that due to the characteristics of the production of cast railway wheels (the wheel rim crystallizes, feeding on liquid metal through a disk, then the disk and hub crystallize), all three zones that are observed in a steel ingot (a zone of fine-grained crust, columnar crystals and equiaxial crystals) are observed and in each element of the cast railway wheel. In the metal of the rim of the cast wheel, the average score of sulfides is 3 points, which does not meet the requirements of GOST 10791: 2016, and the sulfide inclusions in the whole-rolled railway wheel do not exceed 2 on the C scale of GOST 1778-70. It is shown that the microstructure of a cast railway wheel consists of perlite, has a heterogeneous structure (strongly and weakly treated strips), the formation of which is explained by the presence of dendritic segregation, which occurs in the process of crystallization. In the solid-rolled wheel, segregation heterogeneity is weakly expressed, the microstructure is ferritic-pearlitic, homogeneous. The cast wheels of class C according to the strength properties satisfy the requirements of DSTU GOST 10791: 2016 for wheels made of steel grade T, but do not meet the requirements for plastic and viscous characteristics. Originality. The influence of the production method (casting, hot plastic deformation) on the quality indicators of railway wheels has been established. Practical value. Since the metal of a cast railway wheel of class C has low values of reliability indicators, the use of cast railway wheels is possible, apparently, only on closed routes with special operating conditions. Keywords: cast railway wheels, all-rolled railway wheels, microstructure, macrostructure, crystallization, properties.

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Naderi, Nima, and M. Roslan Hashim. "Fabrication of Silicon Carbide Thin Film as a Stabilizing Layer for Improving the Stability of Porous Silicon Photodiodes." Materials Science Forum 717-720 (May 2012): 1283–86. http://dx.doi.org/10.4028/www.scientific.net/msf.717-720.1283.

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This paper investigates the effect of silicon carbide (SiC) thin film as a stabilizing layer on porous silicon (PS) in metal–semiconductor–metal (MSM) photodiodes. Photo-assisted pulsed electrochemical etching method was used to produce the PS layers with large pore density and small crystallite size. As–prepared PS surface was modified with acetylene gas flow in a thermal process (750°C) in order to replace the hydrogen termination by Si–C bonds which is more stable. During the thermal carbonization, carbon atoms penetrated into the silicon lattice forming a thin (~4 nm) SiC layer. Because of high inertness of silicon carbide thin film, thermally carbonized porous silicon layer (TC-PS) was found to be more stable than the freshly prepared PS surfaces. A small reduction in specific surface area was found after carbonization which is due to the small size of acetylene molecules. The FTIR measurements confirmed the presence of SiC bonds in the TC-PS sample. The photocurrent of the fabricated photodiodes based on as-grown PS was lowered under prolonged green laser radiation (532nm, 5mW), but devices based on TC-PS showed more stable I-V characteristics under the same condition even for 120 min of laser exposure.

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Zhang, Bao Lu, Zi Ai Liu, Liu Huang, Jin Long Song, and Yu Wen Sun. "Fabrication of Superhydrophobic Surfaces on Metal Substrates by Nanosecond Laser." Key Engineering Materials 815 (August 2019): 48–53. http://dx.doi.org/10.4028/www.scientific.net/kem.815.48.

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Superhydrophobic surfaces on aluminum, stainless steel, titanium alloy, and copper substrates were fabricated by nanosecond laser etching and fluoroalkylsilane modification. Compared with the existing laser beam machining technologies, such as femtosecond laser etching and picosecond laser etching, for fabricating superhydrophobic surface, the method developed by us is inexpensive and high efficiency. The influence of laser etching parameters on the surface morphology and wettability on the superhydrophobic surfaces were studied through orthogonal analysis method. The good superhydrophobicity with contact angle larger than 160° was achieved on the aforementioned 4 kinds of metals.

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Sahil, Hanny Dahiya, and Kamal Kishor Thakur. "A Review on Synthesis of 2-Dimensional M_n+1X (MXene) materials." E3S Web of Conferences 309 (2021): 01062. http://dx.doi.org/10.1051/e3sconf/202130901062.

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The sequence of 2D transition metal carbides, carbonitrides, and nitrides has gained a lot of interest since the discovery of Ti3C2. About thirty new MXene compounds have been identified, with eight different MXene synthesis methods. The presence of surface terminations such as hydroxyl, oxygen, fluorine, or chlorine in the materials described thus far indicates strong hydrophilicity as well as metallic conductivity MXenes are becoming increasingly popular due to their diverse chemistry, which has sparked a surge in academic interest. We will study and examine the many methods of fabricating MXenes in this review, which will cover everything from MAX phase etching to exfoliation, as well as the best approach to synthesise them and their most current applications.

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Ding, Jingxiu, Ruipeng Zhang, Yuchun Li, David Wei Zhang, and Hongliang Lu. "Investigation of a Macromolecular Additive on the Decrease of the Aluminum Horizontal Etching Rate in the Wet Etching Process." Metals 12, no. 5 (May 8, 2022): 813. http://dx.doi.org/10.3390/met12050813.

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The effect of a macromolecular additive on the etching rate of aluminum (Al) horizontal etching in the wet process was investigated in this work. The horizontal etching in the Al wet etching process became more evident as the film Al becomes thicker. The proposed macromolecule additive, including polyethylene-polypropylene glycol, was added into the Al etchant solution to reduce the Al horizontal etching rate (ER). The undercut problem during metal patterning can then be improved. By using this method, the Al horizontal ER was reduced from 2.0 to 0.9 μm per minute and the selection ratio between the horizontal and vertical ER was effectively improved from 3 to 1.3 times. As well, a hypothesis of physical mechanism for the improvement was proposed. The dispersed particles from the additive emulsion inhibited the transport and exchange of liquid in a horizontal direction. This work provides an alternative reference to improve the selection ratio performance in the metal wet etching process compared with that when using traditional method.

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González, Jesús E., Gabriela de Armas, Jeidy Negrin, Ana M. Beltrán, Paloma Trueba, Francisco J. Gotor, Eduardo Peón, and Yadir Torres. "Influence of Successive Chemical and Thermochemical Treatments on Surface Features of Ti6Al4V Samples Manufactured by SLM." Metals 11, no. 2 (February 11, 2021): 313. http://dx.doi.org/10.3390/met11020313.

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Ti6Al4V samples, obtained by selective laser melting (SLM), were subjected to successive treatments: acid etching, chemical oxidation in hydrogen peroxide solution and thermochemical processing. The effect of temperature and time of acid etching on the surface roughness, morphology, topography and chemical and phase composition after the thermochemical treatment was studied. The surfaces were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction and contact profilometry. The temperature used in the acid etching had a greater influence on the surface features of the samples than the time. Acid etching provided the original SLM surface with a new topography prior to oxidation and thermochemical treatments. A nanostructure was observed on the surfaces after the full process, both on their protrusions and pores previously formed during the acid etching. After the thermochemical treatment, the samples etched at 40 °C showed macrostructures with additional submicro and nanoscale topographies. When a temperature of 80 °C was used, the presence of micropores and a thicker anatase layer, detectable by X-ray diffraction, were also observed. These surfaces are expected to generate greater levels of bioactivity and high biomechanics fixation of implants as well as better resistance to fatigue.

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MIHARA, Masayuki. "Etching Technique for Observation of Microstructures by SUMP Method." JOURNAL OF THE JAPAN WELDING SOCIETY 79, no. 8 (2010): 760–64. http://dx.doi.org/10.2207/jjws.79.760.

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ÖZCAN, MERVE, BİLGEHAN TUNCA, IPEK BILTAŞ, and TUNÇ TUKEN. "The Effect of Different Pre-Surface Finishing Method on the Aluminium Anodization of the 6XXX Series Alloy." Acta Metallurgica Slovaca 27, no. 4 (December 7, 2021): 185–89. http://dx.doi.org/10.36547/ams.27.4.1109.

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In this study, the effect of different pre-surface finishing method on the aluminium anodization was investigated for AA 6063 alloy. Within the scope of pre-surface finishing method which is acidic solution concentrations and process time were determined. Acidic solution was determined by using hydrofluoric acid (HF) and nitric acid (HNO3). Also Gresoff LIM-5 LV chemical was used with different concentrations and process time for degreasing process. The etching effect of acidic solution on aluminium samples was investigated. The optimal etching behaviour was obtained with 1.0% concentration of HF and 3.2% concentration of HNO3 at 10 minutes process time. Also optimal surface properties were observed with 1.0% concentration of Gresoff LIM-5 LV at 12 minutes process time. Then anodic oxidation was performed by using 180 g / L sulfuric acid (H2SO4) and 18 volt (V). Surface morphology of the final aluminium profiles were examined with SEM analysis, Roughness, Gloss and Thickness tests.

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Chen, Xuewen. "Preparation of Au-Ag Bimetals and Large-Size Porous Gold Nanostructured Materials." Advances in Materials Science and Engineering 2021 (December 13, 2021): 1–9. http://dx.doi.org/10.1155/2021/4160735.

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Gold, silver, and other precious metals are very important nonferrous metals and have been widely applied in fields such as electronics, medicine, metallurgy, pharmaceuticals, and transportation. Adjustable properties of precious metals are mainly attributed to controlled synthesis of precious metals by structure, size, composition, and morphology. Synthesis of binary metals focuses on coordination of physical and chemical properties of metal elements in components, with the aim to give full play to the advantages of the two metals. Gold (Au) and silver (Ag) have similar lattice constants, which provide important theoretical basis for obtaining the binary bimetallic nanostructure of the two metals by coreduction at room temperature. Ag–Au alloy was prepared at different molar ratios of Ag+/AuIII, and the bimetallic nanomaterials obtained had similar Ag/Au ratios to the molar ratio at reaction. This suggested that the bimetallic nanomaterials reacted completely, with the maximum average size in Ag90.1–Au9.9 and the minimum average size in Ag83.2–Au16.8 and Ag66.9–Au33.1. Due to the deficiency of conventional etching agents, the “regrowth etching” method was proposed in this study. Specifically, with AuI as the etching agent, the porous gold nanomaterials with the size of more than 300 nm were successfully prepared, achieving the regrowth etching effect and a good structural stability. According to the analysis based on the catalytic reduction reaction with p-nitrophenol, the properties of the large-size porous gold nanomaterials were related to the quantity and size of pores.

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Ogawa, Yuichi, Minoru Uchida, Toru Otsu, Tatsuo Nagai, and Hiroshi Morita. "Pt Etching Method at Low Temperature Using Electrolyzed Sulfuric Acid Solution." Solid State Phenomena 219 (September 2014): 101–4. http://dx.doi.org/10.4028/www.scientific.net/ssp.219.101.

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Recently, in the semiconductor manufacturing industry, NiPt silicide with high conductivity is adopted. However, when removing the NiPt residues in NiPt silicide processing, there is a possibility to damage other metals and silicide. Removal of residual substances must be done with special care. As a conventional method, processing by SPM has been reported by Chur [1]. However, when Pt content is 10% or more, in this method, the wafers must be processed at 150°C for a long period of time. Then, this method may damage a metal gate and silicide. As another method, aqua regia can be used. However, in this method, it takes long time to dissolve NiPt. This paper reports, newly develped Pt etching method using one-step processing of ESA (Electrolyzed Sulfuric Acid) and HCl, and two-step processing using ESA and HCl mixture after HNO3 and H2O2 mixture. This method can treat NiPt silicide at lower temperature within a shorter time than in conventional methods.

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Boughaba, S., and K. Wang. "Fabrication of porous silicon using a gas etching method." Thin Solid Films 497, no. 1-2 (February 2006): 83–89. http://dx.doi.org/10.1016/j.tsf.2005.10.084.

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Dai, Li Ping, Guo Jun Zhang, Shu Ya Wang, and Zhi Qin Zhong. "XPS Study on Barium Strontium Titanate (BST) Thin Films Etching in SF₆/Ar Plasma." Advanced Materials Research 415-417 (December 2011): 1964–68. http://dx.doi.org/10.4028/www.scientific.net/amr.415-417.1964.

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Subscript textReactive ion etching of barium strontium titanate (BST) thin films using an SF6/Ar plasma has been studied. BST surfaces before and after etching were analyzed by X-ray photoelectron spectroscopy to investigate the reaction ion etching mechanism, and chemical reactions had occurred between the F plasma and the Ba, Sr and Ti metal species. Fluorides of these metals were formed and some remained on the surface during the etching process. Ti can be removed completely by chemical reaction because the TiF4by-product is volatile. Minor quantities of Ti-F could still be detected by narrow scan X-ray photoelectron spectra, which was thought to be present in metal-oxy-fluoride(Metal-O-F). These species were investigated from O1sspectra, and a fluoride-rich surface was formed during etching because the high boiling point BaF2and SrF2residues are hard to remove. The etching rate was limited to 14.28nm/min. A 1-minute Ar/10 plasma physical sputtering was carried out for every 4 minutes of surface etching, which effectively removed remaining surface residue. Sequential chemical reaction and sputtered etching is an effective etching method for BST films.

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Fedorov, Aleksandr Sergeevich, Andrey Igorevich Zhitenev, Darya Andreevna Strekalovskaya, Aleksandr Aleksandrovich Kur, and Alexey Aleksandrovich Alkhimenko. "Quantitative Description of Duplex Stainless Steels Microstructure Using Selective Etching." Metals 11, no. 11 (October 31, 2021): 1750. http://dx.doi.org/10.3390/met11111750.

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The properties of duplex stainless steels (DSSs) depend on the ferrite–austenite ratio, on the content of secondary phases and on the contamination with non-metallic inclusions. To assess the quality of DSSs, it is necessary to use an integrated approach which includes controlling for the volume fraction, the morphology and the distribution of all phases and non-metallic inclusions. Samples of several grades of DSSs were obtained using various heat treatments, such as solution annealing and quenching from 1050 to 1250 °C to obtain different amounts of ferrite and to provoke annealing at 850 °C to precipitate σ-phase. As a result, a metallographic technique of phase analysis in DSSs based on selective etching and subsequent structure parameters estimation according to ASTM E1245 was developed. We demonstrated that the developed method of quantitative analysis based on selective etching and metallographic analysis according to ASTM E1245 allows us to obtaining much more accurate results, compared to the point count method described in ASTM E562 and to the XRD method.

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Sudarshan, T. S., M. H. Lim, and S. R. Goode. "A New Method for Etching Molybdenum / Neues Ätzverfahren für Molybdän." Practical Metallography 23, no. 9 (September 1, 1986): 450–57. http://dx.doi.org/10.1515/pm-1986-230908.

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ZANDI, MAJID, MARYAM AMIRHOSEINY, and ABOLGHASEM MOSAYYEBI. "A SIMPLE METHOD TO PREPARE NANOPOROUSSn:PbCOMPOSITE METAL FOAM." Surface Review and Letters 22, no. 03 (May 13, 2015): 1550034. http://dx.doi.org/10.1142/s0218625x15500341.

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A novel and simple approach for preparing nanoporous binder free Sn : Pb composite metal foam has been demonstrated. The anodized metallic composite block was functionalized and also found a nanoporous structure. A scanning electron microscopy (SEM) result shows that the nanoflake-like arrangement has synthesized. The X-ray diffraction (XRD) results confirm the nanoporous structure of the Sn / Pb foam after etching with 6 M NaOH . The prepared Sn : Pb metal foam is able to be used as a super capacitors electrode to offer large areal capacitance with regards to the synergic integration of Sn and Pb metals and the unique nanoporous structure.

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Irgolič, Tomaž, David Potočnik, Mirko Ficko, and Peter Kirbiš. "Microstructural characterization of laser cladded AISI 316 stainless steel on a carbon steel substrate." Advanced Technologies & Materials 44, no. 2 (December 20, 2019): 1–5. http://dx.doi.org/10.24867/atm-2019-2-001.

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Laser engineering net shaping (LENS) is a method of depositing metals into fully shaped parts or for the production of clad layers of noble or wear resistant metals on construction grade steels. In the current work stainless steel was deposited using different combinations of processing parameters such as speed, layer thickness and laser power. The resulting microstructures within the clad layers were then characterized using different etching techniques. Microstructures formed during the SLM process are comprised of columnar grains with a cellular, cellular/dendritic substructure. The exact shape of these grains is difficult to observe with the use of common etching techniques, this is especially true when considering thin cladded layers, with dissimilar etching behavior. For this purpose we compared a variety of different etchants, which attack the ferrite phase or produce a tint effect. Special attention was giving to the delineation of the columnar grains, which under certain processing parameters can exceed the thickness of individual deposited layers.

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Gablech, Imrich, Jan Brodský, Jan Pekárek, and Pavel Neužil. "Infinite Selectivity of Wet SiO2 Etching in Respect to Al." Micromachines 11, no. 4 (March 31, 2020): 365. http://dx.doi.org/10.3390/mi11040365.

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We propose and demonstrate an unconventional method suitable for releasing microelectromechanical systems devices containing an Al layer by wet etching using SiO2 as a sacrificial layer. We used 48% HF solution in combination with 20% oleum to keep the HF solution water-free and thus to prevent attack of the Al layer, achieving an outstanding etch rate of thermally grown SiO2 of ≈1 µm·min−1. We also verified that this etching solution only minimally affected the Al layer, as the chip immersion for ≈9 min increased the Al layer sheet resistance by only ≈7.6%. The proposed etching method was performed in an ordinary fume hood in a polytetrafluorethylene beaker at elevated temperature of ≈70 °C using water bath on a hotplate. It allowed removal of the SiO2 sacrificial layer in the presence of Al without the necessity of handling highly toxic HF gas.

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Fang, Qiuyan, Jian-Zhang Zhou, Dongping Zhan, Kang Shi, Zhao-Wu Tian, and Zhong-Qun Tian. "A novel planarization method based on photoinduced confined chemical etching." Chemical Communications 49, no. 57 (2013): 6451. http://dx.doi.org/10.1039/c3cc42368a.

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Pal, Pooja, Sunil Kumar, and S. K. Singh. "Study of Eutectic Etching Process for Defects Analysis in n type 4H SiC." Defence Science Journal 70, no. 5 (October 8, 2020): 515–19. http://dx.doi.org/10.14429/dsj.70.16361.

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Silicon Carbide (SiC) is a wide bandgap material with unique properties attractive for high power, high temperature applications. The presence of defects in the crystal is a major issue prior device fabrication. These defects affect the performance of the device. To delineate and identify the defects an easy and quick method is desirable. In this study defects delineation in n-type 4H-SiC has been carried out by KOH, KOH+NaOH and KOH+Na2O2 melts. Variation in etch pits size was found at various concentrations of the NaOH in KOH and for different total etching times in the KOH+Na2O2 melt. The eutectic solution etching technique is found to be more efficient to delineate defects and provides control on etching and surface roughness. The etching rates have been estimated under different experimental conditions. Detailed morphological investigations have been performed by wide field high resolution optical microscopy and scanning electron microscopy.

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Swiderska-Sroda, Anna, J. A. Kozubowski, A. Maranda-Niedbala, Ewa Grzanka, Bogdan F. Palosz, A. Presz, Stanislaw Gierlotka, et al. "Investigation of the Microstructure of SiC-Zn Nanocomposites by Microscopic Methods: SEM, AFM and TEM." Solid State Phenomena 101-102 (January 2005): 151–56. http://dx.doi.org/10.4028/www.scientific.net/ssp.101-102.151.

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SiC-Zn nanocomposites with about 20% volume fraction of metal were fabricated by infiltration process under the pressure of 2-8 GPa and at the temperature of 400_1000oC. SiC nanopowders used in the experiments formed loosely agglomerated chains of single crystal nanoparticles. The dimension of the agglomerates was in the micrometer range, the mean grain size was up to tens of nanometers. Microstructural investigations of the nanocomposites were performed at a different resolution levels using scanning, transmission electron microscopy and atomic force microscopy techniques (SEM, TEM, AFM, respectively). SEM observations indicate a presence of nano-dispersed, uniform (on the micrometer scale) mixture of two phases. TEM observations show that distribution of SiC and Zn nanocrystallites is uniform on the nanometer scale. High-resolution TEM images demonstrate an existence of thin (on the order of tens of Angstroms) Zn layers separating SiC grains. AFM images of the mechanically polished samples show a smooth surface with the roughness on the order of the SiC grain size (10-30 nm). After ion etching of some samples the AFM topographs show surface irregularities: periodically spaced hillocks 50-100 nm in height. The size of the SiC grains remains equal to that of the initial powder crystallites. The size of the Zn grains varies in the range of 20-100 nm depending on the initial SiC grain size and the composite fabrication conditions.

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Ouchi, H., A. Tsujimoto, K. Nojiri, K. Hirai, T. Takamizawa, WW Barkmeier, MA Latta, and M. Miyazaki. "Effect of Oxygen Inhibition Layer of Universal Adhesives on Enamel Bond Fatigue Durability and Interfacial Characteristics With Different Etching Modes." Operative Dentistry 42, no. 6 (November 1, 2017): 636–45. http://dx.doi.org/10.2341/16-255-l.

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SUMMARY Objective: The purpose of this study was to evaluate the effect of the oxygen inhibition layer of universal adhesive on enamel bond fatigue durability and interfacial characteristics with different etching modes. Methods: The three universal adhesives used were Scotchbond Universal Adhesive (3M ESPE, St Paul, MN, USA), Adhese Universal (Ivoclar Vivadent, Schaan, Lichtenstein), and G-Premio Bond (GC, Tokyo, Japan). The initial shear bond strength and shear fatigue strength to enamel was determined in the presence and absence of the oxygen inhibition layer, with and without phosphoric acid pre-etching. The water contact angle was also measured in all groups using the sessile drop method. Results: The enamel bonding specimens with an oxygen inhibition layer showed significantly higher (p<0.05) initial shear bond strengths and shear fatigue strengths than those without, regardless of the adhesive type and etching mode. Moreover, the water contact angles on the specimens with an oxygen inhibition layer were significantly lower (p<0.05) than on those without, regardless of etching mode. Conclusion: The results of this study suggest that the oxygen inhibition layer of universal adhesives significantly increases the enamel bond fatigue durability and greatly changes interfacial characteristics, suggesting that the bond fatigue durability and interfacial characteristics of these adhesives strongly rely on its presence.

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NIU, Xin-huan, Guo-qi LU, Wei-lian ZHANG, Jin-yong GAO, and Yu-ling LIU. "Dislocation of Cz-sapphire substrate for GaN growth by chemical etching method." Transactions of Nonferrous Metals Society of China 16 (June 2006): s187—s190. http://dx.doi.org/10.1016/s1003-6326(06)60172-6.

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Sato, Yuma, Hiroshi Koshikawa, Shunya Yamamoto, Masaki Sugimoto, Shin-ichi Sawada, and Tetsuya Yamaki. "Fabrication of Size- and Shape-Controlled Platinum Cones by Ion-Track Etching and Electrodeposition Techniques for Electrocatalytic Applications." Quantum Beam Science 5, no. 3 (July 1, 2021): 21. http://dx.doi.org/10.3390/qubs5030021.

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The micro/nanocone structures of noble metals play a critical role as heterogeneous electrocatalysts that provide excellent activity. We successfully fabricated platinum cones by electrodeposition using non-penetrated porous membranes as templates. This method involved the preparation of template membranes by the swift-heavy-ion irradiation of commercially available polycarbonate films and subsequent chemical etching in an aqueous NaOH solution. The surface diameter, depth, aspect ratio and cone angle of the resulting conical pores were controlled in the ranges of approximately 70–1500 nm, 0.7–11 μm, 4–12 and 5–13°, respectively, by varying the etching conditions, which finally produced size- and shape-controlled platinum cones with nanotips. In order to demonstrate the electrocatalytic activity, electrochemical measurements were performed for the ethanol oxidation reaction. The oxidation activity was found to be up to 3.2 times higher for the platinum cone arrays than for the platinum plate. Ion-track etching combined with electrodeposition has the potential to be an effective method for the fabrication of micro/nanocones with high electrocatalytic performance.

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Premkumar, Jeromerajan, and Narasimalu Srikanth. "Measurement of Deformed Aluminum Layer of Bond Pads in Cu-Wire Bonded Integrated Circuit Devices Using a Etching Approach." Practical Metallography 45, no. 11 (November 1, 2008): 546–53. http://dx.doi.org/10.1515/pm-2008-0083.

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Abstract In the copper ball bond process, aluminum squeezes out under the ball deformation process since it is softer than copper. The final thickness of the copper ball decides the overall strength of the bond and hence knowledge of its final thickness helps to optimize the ball bond force during the bonding process. An etching method is developed for the analysis of the squeezed aluminum beneath the copper wire ball bond. The aluminum remnant obtained from the etching method is compared with that from the conventional cross-section method. It was found that the results are comparable and the present developed etched method is simple and elegant.

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Yurchenko, A. N., Yu N. Simonov, and O. V. Efimova. "Determination of the Complex Structure of Structural Steel by the Method of Color Etching." Metal Science and Heat Treatment 61, no. 9-10 (January 2020): 622–27. http://dx.doi.org/10.1007/s11041-020-00470-y.

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38

Nowak, Wojciech J. "The Use of Ion Milling for Surface Preparation for EBSD Analysis." Materials 14, no. 14 (July 16, 2021): 3970. http://dx.doi.org/10.3390/ma14143970.

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An electron backscattered diffraction (EBSD) method provides information about the crystallographic structure of materials. However, a surface subjected to analysis needs to be well-prepared. This usually requires following a time-consuming procedure of mechanical polishing. The alternative methods of surface preparation for EBSD are performed via electropolishing or focus ion beam (FIB). In the present study, plasma etching using a glow discharge optical emission spectrometer (GD-OES) was applied for surface preparation for EBSD analysis. The obtained results revealed that plasma etching through GD-OES can be successfully used for surface preparation for EBSD analysis. However, it was also found that the plasma etching is sensitive for the alloy microstructure, i.e., the presence of intermetallic phases and precipitates such as carbides possess a different sputtering rate, resulting in non-uniform plasma etching. Preparation of the cross-section of oxidized CM247 revealed a similar problem with non-uniformity of plasma etching. The carbides and oxide scale possess a lower sputtering rate than the metallic matrix, which caused formation of relief. Based on obtained results, possible resolutions to suppress the effect of different sputtering rates are proposed.

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Liao, Y. S., and L. C. Chen. "A method of etching and powder blasting for microholes on brittle materials." Journal of Materials Processing Technology 209, no. 9 (May 2009): 4390–94. http://dx.doi.org/10.1016/j.jmatprotec.2008.11.032.

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40

Ennas, Guido, Maria F. Casula, Sergio Marras, Gabriele Navarra, Alessandra Scano, and Giaime Marongiu. "Characterization of FeOOH Nanoparticles and Amorphous Silica Matrix in an FeOOH-SiO2Nanocomposite." Journal of Nanomaterials 2008 (2008): 1–6. http://dx.doi.org/10.1155/2008/361816.

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A nanocomposite with an FeOOH/SiO2ratio equal to 17.7 wt% and the pertinent matrix, obtained by etching away the nanoparticles through reaction with hydrochloric acid, were investigated by XRD, TGA-DTA, heliostereopicnometry, BET, and TEM techniques. The study shows the presence in the nanocomposite of ferrihydrite nanoparticles phase with average dimensions around 4 nm. The FeOOH nanoparticles structure was analyzed by synchrotron X-ray diffraction data using the distribution difference curve method. The porous structure of the matrix resulting by etching away the nanoparticles differs significantly from that of a pureSiO2sample obtained by hydrolysis of TEOS under the same operative conditions followed in the nanocomposite preparation.

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Zhang, Dong, Ping Shen, Jian-bo Xie, Jin-min An, Zong-ze Huang, and Jian-xun Fu. "A method for observing tridimensional morphology of sulfide inclusions by non-aqueous solution electrolytic etching." Journal of Iron and Steel Research International 26, no. 3 (September 18, 2018): 275–84. http://dx.doi.org/10.1007/s42243-018-0142-z.

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García, L., C. Dietz, J. M. Gómez de Salazar, J. A. Martínez, and A. J. Criado. "Coloured Metallography of Ti-6Al-4V Alloys Using Phtalocyanine Blue." Practical Metallography 53, no. 6 (June 1, 2016): 340–51. http://dx.doi.org/10.1515/147.110399.

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Abstract This work presents a method to improve visualisation of metallographic structures in titanium containing alloys. After conventional selective chemical etching with Kroll’s reagent, the surface of the sample specimen is manually dyed with a phtalocyanine based lacquer. The results are highly detailed and sharp coloured images when investigated with Optical Microscopy, providing much more information compared to the grey shaded, etching only approach.

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Chen, Chen, Li He, Chengxin Jiang, Lingxiu Chen, Hui Shan Wang, Xiujun Wang, Ziqiang Kong, et al. "Directional etching for high aspect ratio nano-trenches on hexagonal boron nitride by catalytic metal particles." 2D Materials 9, no. 2 (March 1, 2022): 025015. http://dx.doi.org/10.1088/2053-1583/ac5461.

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Abstract Stimulated by the attractive performance of multi-dimensional heterostructures involving hexagonal boron nitride (hBN), intense attentions have been paid to creation of sharp boundary/interface, which could bring hBN nano-structures additional appealing physical properties. However, the lack of controllable synthesis limits further experimental investigation on hBN nano-structures. Here, the directional etching of transitional metal nano-particles (NPs) on the surface of hBN to produce nano-trenches with sharp edges was systematic investigated. It is found that, only Pt and Ir NPs can produce armchair-oriented nano-trenches at low H2 partial pressure, while other transitional metals lead to zigzag oriented nano-trenches. The density and width of the nano-trenches always increase with etching temperature and the pre-treated solution concentration while the trench orientation depends on both H2 partial pressure and etching temperature. The aspect ratio of nano-trenches may reach several thousand under optimized conditions. The method exhibited here shines a light on edge-selective patterning of 2D crystals.

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Bochniak, Włodzimierz, Paweł Ostachowski, Andrzej Korbel, and K. Pieła. "Superplastic Flow of Metals Extruded by KoBo Method." Materials Science Forum 667-669 (December 2010): 1039–44. http://dx.doi.org/10.4028/www.scientific.net/msf.667-669.1039.

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The extrusion of metals by the KoBo method, which is a new technological solution, allows to perform the process at low temperature with severe plastic deformation (SPD) under cyclic change of deformation path conditions. Apart from the localized plastic flow in shear bands intensive generation of point defects (self interstitials) takes place. It is important that excessive concentration of interstitial atoms is preserved in extruded products and often takes the shape of nanoclusters. Their presence causes that the effect of superplasticity (e.g. about 800% elongation of aluminum alloy 7075) does not require nanometric sizes of the grains and appears in metals extruded by the KoBo method with grains of over dozen or even several dozen micrometers. The results suggest the necessity to verify the mechanisms currently considered as decisive of the superplastic flow of metals.

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Kubilay, Ceylan, Havva Kazdal Zeytin, and Hüseyin Aydin. "The Microstructural Characterization of Dual Phase Steel with the Method of Chemical Etching." Practical Metallography 45, no. 12 (December 2008): 610–18. http://dx.doi.org/10.3139/147.100407.

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Franz, Mathias, Romy Junghans, Paul Schmitt, Adriana Szeghalmi, and Stefan E. Schulz. "Wafer-level integration of self-aligned high aspect ratio silicon 3D structures using the MACE method with Au, Pd, Pt, Cu, and Ir." Beilstein Journal of Nanotechnology 11 (September 23, 2020): 1439–49. http://dx.doi.org/10.3762/bjnano.11.128.

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The wafer-level integration of high aspect ratio silicon nanostructures is an essential part of the fabrication of nanodevices. Metal-assisted chemical etching (MACE) is a promising low-cost and high-volume technique for the generation of vertically aligned silicon nanowires. Noble metal nanoparticles were used to locally etch the silicon substrate. This work demonstrates a bottom-up self-assembly approach for noble metal nanoparticle formation and the subsequent silicon wet etching. The macroscopic wafer patterning has been done by using a poly(methyl methacrylate) masking layer. Different metals (Au, Pt, Pd, Cu, and Ir) were investigated to derive a set of technologies as platform for specific applications. Especially, the shape of the 3D structures and the resulting reflectance have been investigated. The Si nanostructures fabricated using Au nanoparticles show a perfect light absorption with a reflectance below 0.3%. The demonstrated technology can be integrated into common fabrication processes for microelectromechanical systems.

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SAITO, Hideo, and Fumio MORITO. "Visualization of Boron in Molybdenum by α-rays Track Etching Method and Tritium Autoradiography." Tetsu-to-Hagane 89, no. 7 (2003): 750–57. http://dx.doi.org/10.2355/tetsutohagane1955.89.7_750.

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Deshmukh, Suparna. "Studies on Precision and Accuracy In Microdetermination of Transition Metals Using Ternary Complex EAB-CTAB-Metals." Oriental Journal of Chemistry 34, no. 4 (July 25, 2018): 1930–36. http://dx.doi.org/10.13005/ojc/3404029.

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Complexometric and Analytical studies have carried out by forming ternary complex between Eriochrome Azurol B, and Cetyl Trimethyl Ammonium Bromide CTAB; and some transition metal ions mainly Cu2+, Ni2+ and Cd2+. The absorption spectra of Eriochrome Azurol B ,EAB; a triphenylmethane dye, has studied in the presence as well as in the absence of surfactant, Cetyl Trimethyl Ammonium Bromide, CTAB at pH values ranging from pH 1.00 to 12.00. Hypsochromic shift is observed in the absorption spectra in the presence of surfactant pK values i.e. dissociation constant values are found to decreased, in the presence of surfactant is observed. Composition of chelates EAB:CTAB:Metal is found to be 1:1:1, and effect of foreign ions such as chlorides, nitrates; and sulphates of sodium, potassium and ammonium; has been studied in detail. Stability constants of the chelates are determined. Sensitivity and Stability of chelates formedincreases in the presence of surfactant. Various analytical parameters including range of adherence to Beers Law, Molar Extinction Constants, Sandells Sensitivity, were studied for all systems by its interaction with and without CTAB. Precision and Accuracy of the method suggested for microdetermination of metal ions is determined and found out that method is both precise as well as accurate.

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Krakow, William, and Victor Castaño. "A new method for preparing tilt grain boundaries in thin vapor-deposited films." Proceedings, annual meeting, Electron Microscopy Society of America 45 (August 1987): 280–81. http://dx.doi.org/10.1017/s0424820100126263.

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In the past the electron microscope samples used to study tilt grain boundaries and interfaces were prepared from bulk samples grown from the melt which were then cut, polished and thinned by ion milling or chemical jet etching. This technique is also employed routinely in preparing crossectional semiconductor materials and metals. Another technique to prepare tilt boundaries in metals is to fuse two thin single crystal films each on substrates by heating and forming twist boundaries (e.g. Au (100)). Then, the boundary which forms at the composite film midplane, migrates to one of the two films surfaces having many island grains separated by tilt boundaries perpendicular to the foils’ surface. One of the present authors has carried this technique further by being able to perform this process directly in the microscope and observe the boundary migration when the total film thickness, in the case of Au, was ∼250Å. The technique is limited to this composite thickness because small holes develop in thinner films which thin rapidly become discontinuous when heated in-situ.

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Blümke, R., and C. Müller. "Use of duplex microstructures in steel for estimation of plastic deformation in high-speed machining chips." International Journal of Materials Research 93, no. 11 (November 1, 2002): 1119–22. http://dx.doi.org/10.1515/ijmr-2002-0192.

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Abstract It is shown that chip formation in high-speed milling of a steel remains unaffected by the presence of a volume fraction of about 10 % ferrite to either martensitic or pearlitic microstructures. Ferrite grains remain visible within the chips and can, therefore, be used for an estimation of the local plastic deformation. In case of the martensite structure, a deformation of 3000 % was measured in the white etching secondary shear zone, while a considerable amount of deformation even takes place within chip segments. The presence of ferrite grains within the white layer is an indication of a thermally-induced phase transformation occurring within the secondary shear zone of the chips.

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Journal articles on the topic 'Method of etching in the presence of metals'

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