Journal articles: 'Microstructural analysis'

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Bhakar, Ashok, Pooja Gupta, P. N. Rao, M. K. Swami, Pragya Tiwari, Tapas Ganguli, and S. K. Rai. "Line profile analysis of synchrotron X-ray diffraction data of iron powder with bimodal microstructural profile parameters." Journal of Applied Crystallography 54, no. 2 (March 18, 2021): 498–512. http://dx.doi.org/10.1107/s1600576721000601.

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Room-temperature synchrotron X-ray diffraction and subsequent detailed line profile analysis of Fe powder were performed for microstructural characterization. The peak shapes of the diffraction pattern of Fe were found to be super-Lorentzian in nature and the peak widths were anisotropically broadened. These peak profile features of the diffraction pattern are related to the microstructural parameters of the material. In order to elucidate these features of the diffraction pattern, detailed line (peak) profile analyses were performed using the Rietveld method, modified Williamson–Hall plots and whole powder pattern modelling (WPPM), and related microstructural parameters were determined. Profile fitting using the Rietveld and WPPM methods with a single microstructural (unimodal) model shows systematic deviation from the experimentally observed diffraction pattern. On the basis of Rietveld analysis and microstructural modelling it is revealed that the microstructure of Fe consists of two components (bimodal profile). The microstructural parameters of crystallite/domain size distribution, dislocation density, nature of dislocations and phase fraction were evaluated for both components. The results obtained using different methods are compared, and it is shown that diffraction peak profile analysis is capable of modelling such inhomogeneous bimodal microstructures.

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Ott, J., A. Burghardt, D. Britz, S. Majauskaite, and F. Mücklich. "Qualitative and Quantitative Microstructural Analysis of Copper for Sintering Process Optimization in Additive Manufacturing Applications." Practical Metallography 58, no. 1 (January 1, 2021): 32–47. http://dx.doi.org/10.1515/pm-2020-0002.

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Abstract This work will present possibilities for the characterization of copper powder green bodies and sintered copper microstructures during pressureless sintering. The introduction of new parameters to microstructural characterization based on qualitative and quantitative microstructural analysis will facilitate the systematic optimization of the sintering process. As a result of the specific evaluation of the microstructure evolution, conventional isothermal sintering could be successfully replaced by multi-step temperature profiles, thus achieving sintering densities of more than 99 % by simultaneously reducing process time. This systematic optimization of the sintering process of Cu through specific microstructural analysis may now be applied to sinter-based manufacturing technologies such as Binder Jetting and Metal Powder Injection Moulding, enabling the manufacture of complex and highly conductive Cu parts for applications in electronics.

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Höche, Nils, Eric O. Walliser, Niels J. de Winter, Rob Witbaard, and Bernd R. Schöne. "Temperature-induced microstructural changes in shells of laboratory-grown Arctica islandica (Bivalvia)." PLOS ONE 16, no. 2 (February 26, 2021): e0247968. http://dx.doi.org/10.1371/journal.pone.0247968.

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Bivalve shells are increasingly used as archives for high-resolution paleoclimate analyses. However, there is still an urgent need for quantitative temperature proxies that work without knowledge of the water chemistry–as is required for δ18O-based paleothermometry–and can better withstand diagenetic overprint. Recently, microstructural properties have been identified as a potential candidate fulfilling these requirements. So far, only few different microstructure categories (nacreous, prismatic and crossed-lamellar) of some short-lived species have been studied in detail, and in all such studies, the size and/or shape of individual biomineral units was found to increase with water temperature. Here, we explore whether the same applies to properties of the crossed-acicular microstructure in the hinge plate of Arctica islandica, the microstructurally most uniform shell portion in this species. In order to focus solely on the effect of temperature on microstructural properties, this study uses bivalves that grew their shells under controlled temperature conditions (1, 3, 6, 9, 12 and 15°C) in the laboratory. With increasing temperature, the size of the largest individual biomineral units and the relative proportion of shell occupied by the crystalline phase increased. The size of the largest pores, a specific microstructural feature of A. islandica, whose potential role in biomineralization is discussed here, increased exponentially with culturing temperature. This study employs scanning electron microscopy in combination with automated image processing software, including an innovative machine learning–based image segmentation method. The new method greatly facilitates the recognition of microstructural entities and enables a faster and more reliable microstructural analysis than previously used techniques. Results of this study establish the new microstructural temperature proxy in the crossed-acicular microstructures of A. islandica and point to an overarching control mechanism of temperature on the micrometer-scale architecture of bivalve shells across species boundaries.

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Nolan, T. P., R. Sinclair, T. Yamashita, and R. Ranjan. "Correlation of micro-structural, micro-chemical and micro-magnetic properties of longitudinal recording media using CM20FEG Lorentz TEM." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 892–93. http://dx.doi.org/10.1017/s042482010017219x.

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Cobalt alloy on chromium thin film magnetic media are used in industry computer hard disk drives because of their large values of coercivity (Hc), remanent magnetization (Mr), squareness (S*), and relatively low noise. The magnetic performance depends strongly on processing conditions and the resulting nanometer scale microstructure.A complete structure-processing-properties analysis requires effective measurement of magnetic and microstructural properties. To date, most structure-properties analyses have involved correlation of bulk magnetic (hysteresis loop) properties and magnetic recording measurements with physical microstructures observed by high-resolution SEM and TEM.The nanoscale microstructural features that dramatically affect magnetic properties are difficult to observe but careful TEM analysis has been used to observe subtle, important differences in the atomic scale physical microstructure. Even these impressive capabilities are becoming insufficient for continued development of improved magnetic recording media. Microstructural design is moving into a regime where appropriate control of magnetic properties requires control of elemental composition and second phase formation as well as crystallography and morphology, at near-atomic levels.

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Dahmen, U., N. Thangaraj, and R. Kilaas. "Quantitative TEM analysis of microstructural anisotropy." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 682–83. http://dx.doi.org/10.1017/s0424820100171146.

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Preferred orientation of grain boundaries or interfaces in solids is an important indicator of anisotropy in boundary energy or kinetics. The present study is part of an ongoing investigation of faceting in thin films with the mazed bicrystal microstructure which possesses several unique features that are difficult to measure with standard parameters such as grain size distribution. One of the important characteristics of this microstructure is the degree and type of anisotropy. Figure 1 shows a micrograph with a typical mazed bicrystal microstructure. Only two grain orientations with about equal volume fraction are seen in black and white contrast, respectively. It is apparent that unlike a normal polycrystalline thin film, individual grains in this microstructure have unusual convoluted shapes with both concave and convex regions.The standard stereological method to measure microstructural anisotropy is the rose plot generated from a count of intersections with a reference grid overlaid on the micrograph at different angles.

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Beh, Chong You, Ee Meng Cheng, Xiao Jian Tan, Nashrul Fazli Mohd Nasir, Mohd Shukry Abdul Majid, Mohd Ridzuan Mohd Jamir, Shing Fhan Khor, Kim Yee Lee, and Che Wan Sharifah Robiah Mohamad. "Complex Impedance and Modulus Analysis on Porous and Non-Porous Scaffold Composites Due to Effect of Hydroxyapatite/Starch Proportion." Polymers 15, no. 2 (January 8, 2023): 320. http://dx.doi.org/10.3390/polym15020320.

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This study aims to investigate the electric responses (complex modulus and complex impedance analysis) of hydroxyapatite/starch bone scaffold as a function of hydroxyapatite/starch proportion and the microstructural features. Hence, the non-porous and porous hydroxyapatite/starch composites were fabricated with various hydroxyapatite/starch proportions (70/30, 60/40, 50/50, 40/60, 30/70, 20/80, and 10/90 wt/wt%). Microstructural analysis of the porous hydroxyapatite/starch composites was carried out by using scanning electron microscopy. It shows that the formation of hierarchical porous microstructures with high porosity is more significant at a high starch proportion. The complex modulus and complex impedance analysis were conducted to investigate the electrical conduction mechanism of the hydroxyapatite/starch composites via dielectric spectroscopy within a frequency range from 5 MHz to 12 GHz. The electrical responses of the hydroxyapatite/starch composites are highly dependent on the frequency, material proportion, and microstructures. High starch proportion and highly porous hierarchical microstructures enhance the electrical responses of the hydroxyapatite/starch composite. The material proportion and microstructure features of the hydroxyapatite/starch composites can be indirectly reflected by the simulated electrical parameters of the equivalent electrical circuit models.

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Charles Murgau, Corinne, Andreas Lundbäck, Pia Åkerfeldt, and Robert Pederson. "Temperature and Microstructure Evolution in Gas Tungsten Arc Welding Wire Feed Additive Manufacturing of Ti-6Al-4V." Materials 12, no. 21 (October 28, 2019): 3534. http://dx.doi.org/10.3390/ma12213534.

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In the present study, the gas tungsten arc welding wire feed additive manufacturing process is simulated and its final microstructure predicted by microstructural modelling, which is validated by microstructural characterization. The Finite Element Method is used to solve the temperature field and microstructural evolution during a gas tungsten arc welding wire feed additive manufacturing process. The microstructure of titanium alloy Ti-6Al-4V is computed based on the temperature evolution in a density-based approach and coupled to a model that predicts the thickness of the α lath morphology. The work presented herein includes the first coupling of the process simulation and microstructural modelling, which have been studied separately in previous work by the authors. In addition, the results from simulations are presented and validated with qualitative and quantitative microstructural analyses. The coupling of the process simulation and microstructural modeling indicate promising results, since the microstructural analysis shows good agreement with the predicted alpha lath size.

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Pinheiro, Bruno C. A., and J. N. F. Holanda. "Microstructural Analysis of Petroleum Waste Containing Ceramic Tile." Materials Science Forum 591-593 (August 2008): 845–48. http://dx.doi.org/10.4028/www.scientific.net/msf.591-593.845.

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In this work is done a study on the sintered microstructure of ceramic tile paste incorporated with petroleum waste. The raw materials used were kaolin, sodic feldspar, quartz and petroleum waste. The ceramic tiles containing up to 5 wt% petroleum waste were prepared by uniaxial pressing and sintered at 1200°C. The microstructural evolution was examined by SEM. In addition, water absorption, linear shrinkage, and sintered density were determined. The results showed that the microstructure of the ceramic tiles is influenced by the added petroleum waste.

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Agnani, M., O. L. DeNonno, K. O. Findley, and S. W. Thompson. "Quantitative Analysis of Microstructural Refinement in Simulated Carburized Microstructures." Journal of Materials Engineering and Performance 29, no. 6 (March 9, 2020): 3551–59. http://dx.doi.org/10.1007/s11665-020-04714-z.

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Shin, Jun Ho, Nam Yong Jee, Leslie J. Struble, and R. James Kirkpatrick. "Modeling Alkali-Silica Reaction Using Image Analysis and Finite Element Analysis." Advanced Materials Research 250-253 (May 2011): 1050–53. http://dx.doi.org/10.4028/www.scientific.net/amr.250-253.1050.

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The objective of this study is to develop a numerical model based on microstructural images of concrete and fundamental material properties of each constituent of concrete subjected to alkali-silica reaction (ASR). A microstructure-based finite element approach is employed directly to analyze the mechanical response of concrete to ASR. The modeling work involves acquiring and processing of microstructural images of specimens suffering from ASR using scanning electron microscopy, and implementing finite element program to analyze the microstructural images. The formulation of this model is based on pressure caused by the ASR product and on properties such as Young’s modulus and Poisson’s ratio. The finite element analysis program used to simulate structural behavior of structures attacked by ASR is object-oriented finite element developed at National Institute of Standards and Technology. The numerical results from this model are compared with experimental data, which have been measured using ASTM standard test C1260. The results show that the development and widening of cracks by formation and swelling of ASR gel cause the majority of expansion of mortar specimens rather than elastic elongation due to gel swelling.

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Hu, Xiaobing, Jiajun Zhao, Yiming Chen, Yujian Wang, Junjie Li, Qingfeng Wu, Zhijun Wang, and Jincheng Wang. "Structure-property modeling scheme based on optimized microstructural information by two-point statistics and principal component analysis." Journal of Materials Informatics 2, no. 1 (2022): 5. http://dx.doi.org/10.20517/jmi.2022.05.

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Construction of the structure-property (SP) relationship is an important tenet during materials development. Optimizing microstructural information is a necessary and challenging task in understanding and improving this linkage. To solve the problem that the experimental microstructures with a small size usually fail to represent the entire sample structure, a data-driven scheme integrating two-point statistics, principal component analysis, and machine learning was developed to reasonably construct a representative volume element (RVE) set from the small microstructures and extract optimized structural information. Based on the elaborate quantitative metrics and method, this kind of RVE set was successfully constructed on an experimental microstructure dataset of ferrite heat-resistant steels. Moreover, to remove redundant information included in two-point statistics, the critical threshold of the tolerance factor related to the coherence length in microstructures was determined to be 0.005. An accurate SP linkage was finally established (mean absolute error < 6.28 MPa for yield strength). This scheme was further validated on two other simulated and experimental datasets, which proved that it can offer scientific nature, reliability, and universality compared to traditional strategies. This scheme has a bright application prospect in microstructure classification, property prediction, and alloy design.

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YEOM, JONG-TAEK, JEOUNG HAN KIM, JAE-KEUN HONG, NHO-KWANG PARK, and CHONG SOO LEE. "INFLUENCE OF INITIAL MICROSTRUCTURE ON HOT WORKABILITY OF Ti-6Al-4V ALLOY." International Journal of Modern Physics B 23, no. 06n07 (March 20, 2009): 808–13. http://dx.doi.org/10.1142/s0217979209060063.

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Hot workability of Ti -6 Al -4 V alloy with different initial microstructures was investigated by considering processing maps and the dynamic material deformation behavior. The emphasis has been focused on the effect of initial microstructure (equiaxed versus bimodal structure). Process maps were generated using the dynamic material model (DMM), unifying the relationships between constitutive deformation behavior, hot workability and microstructures evolution. Also, the flow instability was investigated using the various flow instability criteria and microstructural analysis. To establish the processing maps with different initial microstructures, high temperature compression tests were carried out at various temperatures and strain rates up to a true strain of 0.7. Microstructural changes occurring during the deformation were analyzed in terms of high temperature deformation mechanisms. Finally the useful instability criterion for predicting the forming defects was suggested through the compression test results with different temperatures and strain rates.

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Moayedi, H., S. Kazemian, and A. H. Vakili. "The Surface Electrical and Microstructure Analysis of Peat Treated with Cement." Advanced Materials Research 629 (December 2012): 455–60. http://dx.doi.org/10.4028/www.scientific.net/amr.629.455.

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Peat usually undergo large secondary settlements depending on the amount of organic content present in the soil. This is because of its special microstructure. The microstructure of peat has interdependence with mechanical and physical characteristics, such as compressive and tensile strength, and water retention. In the present research, peat samples were admixed with different concentrations of cement to enhance its physical, chemical, electrical, and microstructural properties. As a result, the surface electrical of the peat colloids influence the rate of flocculation, and in turn further strength achievement. The results is in contrary with the microstructural analysis that performed by SEM and EDX on the treated peat.

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Kim, Won Yong. "High Temperature Strength of Ni-Al-Cr Based Alloys Containing Refractory Elements for Advanced Die Materials." Materials Science Forum 539-543 (March 2007): 1589–94. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1589.

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Microstructures and mechanical properties of Ni3Al based intermetallic alloys produced by vacuum arc melting and vacuum induction melting were investigated in terms of phase analysis using scanning electron microscope (SEM) equipped with energy dispersive X-ray spectroscopy (EDS), X-ray diffractometer and tensile test machine. The duplex microstructural feature consisting of γ’ matrix phase and small intermetallic dispersoids was observed to be distributed over the whole microstructure in the Zr and/or Mo-added samples. From the SEM-EDS analysis of the alloys, it is clearly confirmed that the Mo is solved both into γ’ matrix phase and intermetallic phase while Zr has a role to form an intermetallic Ni5Zr phase for the entire alloys investigated. The ultimate tensile strength of the present alloy was superior to iron-based and Ni-based die materials especially in the high temperature region. The mechanical results obtained will be discussed in correlation with microstructural observations, phase analyses.

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Zhao, Dongfu, Penghe Jia, Pingying Hou, Huixuan Liu, Rundong Zhao, and Haijing Gao. "Microstructural analysis to uniaxial low cyclic compression of high-strength concrete after high temperature." Advances in Structural Engineering 22, no. 3 (September 25, 2018): 779–91. http://dx.doi.org/10.1177/1369433218800205.

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The uniaxial compressive cycling tests of high-strength concrete after high temperature under different stress were carried out using the electrohydraulic servo-controlled fatigue testing system. The investigation focused on low-cycle fatigue to figure out the relationship between microstructural development and number of cycles. The variation in microstructure during uniaxial compressive fatigue process was systematically analyzed and compared using ultrasonic, micro-hardness test, mercury intrusion porosimetry, and scanning electron microscopy. It is found that at the same life ratio, the cumulative fatigue damage caused by the lower stress is greater than that caused by the higher stress, and the four kinds of test methods used to measure the microstructure are consistent, interrelated, and confirmed with each other well. Through the nonlinear regression analysis of fatigue residual strain and microstructural parameters, the relationship models between them were established. Furthermore, the fatigue damage models based on microstructural parameters were established. On this basis, both the dynamic evolution process and damage mechanism of microstructure during uniaxial compressive fatigue were further revealed.

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Welzel, Udo, and Eric J. Mittemeijer. "The analysis of homogeneously and inhomogeneously anisotropic microstructures by X-ray diffraction." Powder Diffraction 20, no. 4 (December 2005): 376–92. http://dx.doi.org/10.1154/1.2138066.

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The microstructure of materials is generally, macroscopically, anisotropic and/or inhomogeneous. Traditional diffraction analyses do not take into account this anisotropy and/or inhomogeneity of microstructural features. Thus obtained results can be incomplete, ambiguous, or even erroneous. In this work instrumental requirements (application of parallel beam diffractometers with X-ray lenses or X-ray mirrors and parallel-plate collimators in the laboratory and at synchrotron beam lines) and methodological approaches for the diffraction analysis of anisotropic and inhomogeneous microstructures have been discussed and have been illustrated on the basis of two experimental examples: analysis of the anisotropic nature of the structural imperfection of a sputterdeposited Ti3Al layer and analysis of the anisotropic and inhomogeneous elastic grain interaction in a sputter-deposited Ni layer.

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Hyde, Jonathan M., Gérald DaCosta, Constantinos Hatzoglou, Hannah Weekes, Bertrand Radiguet, Paul D. Styman, Francois Vurpillot, et al. "Analysis of Radiation Damage in Light Water Reactors: Comparison of Cluster Analysis Methods for the Analysis of Atom Probe Data." Microscopy and Microanalysis 23, no. 2 (January 30, 2017): 366–75. http://dx.doi.org/10.1017/s1431927616012678.

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AbstractIrradiation of reactor pressure vessel (RPV) steels causes the formation of nanoscale microstructural features (termed radiation damage), which affect the mechanical properties of the vessel. A key tool for characterizing these nanoscale features is atom probe tomography (APT), due to its high spatial resolution and the ability to identify different chemical species in three dimensions. Microstructural observations using APT can underpin development of a mechanistic understanding of defect formation. However, with atom probe analyses there are currently multiple methods for analyzing the data. This can result in inconsistencies between results obtained from different researchers and unnecessary scatter when combining data from multiple sources. This makes interpretation of results more complex and calibration of radiation damage models challenging. In this work simulations of a range of different microstructures are used to directly compare different cluster analysis algorithms and identify their strengths and weaknesses.

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Della Valle, R. G., D. Gazzillo, R. Frattini, and G. Pastore. "Microstructural analysis of simulatedNi33Y67glass." Physical Review B 49, no. 18 (May 1, 1994): 12625–32. http://dx.doi.org/10.1103/physrevb.49.12625.

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Khomenko, A. I., and E. V. Khomenko. "Microstructural analysis software package." Powder Metallurgy and Metal Ceramics 46, no. 1-2 (January 2007): 100–104. http://dx.doi.org/10.1007/s11106-007-0016-6.

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Santos, Dagoberto Brandão, Élida G. Neves, and Elena V. Pereloma. "Effect of Processing Route on Mechanical Behavior of C-Mn Multiphase High Strength Cold Rolled Steel." Materials Science Forum 539-543 (March 2007): 4375–80. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.4375.

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The multiphase steels have complex microstructures containing polygonal ferrite, martensite, bainite, carbide and a small amount of retained austenite. This microstructure provides these steels with a high mechanical strength and good ductility. Different thermal cycles were simulated in the laboratory in order to create the microstructures with improved mechanical properties. The samples were heated to various annealing temperatures (740, 760 or 780°C), held for 300 s, and then quickly cooled to 600 or 500°C, where they were soaked for another 300 s and then submitted to the accelerated cooling process, with the rates in the range of 12-30°C/s. The microstructure was examined at the end of each processing route. The mechanical behavior evaluation was made by microhardness testing. The microstructural characterization involved optical microscopy (OM), X-ray diffraction (XRD), scanning electron microscopy (SEM) with electron backscattering diffraction (EBSD) and transmission electron microscopy (TEM). The use of multiple regression analysis allowed the establishment of quantitative relationship between the microstructural parameters, cooling rates and mechanical properties of the steel.

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Hoppe, R. H. W., and S. I. Petrova. "Multi-scale Method for the Crack Problem in Microstructural Materials." Computational Methods in Applied Mathematics 10, no. 1 (2010): 69–86. http://dx.doi.org/10.2478/cmam-2010-0003.

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AbstractThe paper deals with the numerical computation of a crack problem posed on microstructural heterogeneous materials containing multiple phases in the microstructure. The failure of such materials is a natural multi-scale effect since cracks typically nucleate in regions of defects on the microscopic scale. The modeling strategy for solving the crack problem concerns simultaneously the macroscopic and microscopic models. Our approach is based on an efficient combination of the homogenization technique and the mesh superposition method (s-version of the finite element method). The homogenized model relies on a double-scale asymptotic expansion of the displacement field. The mesh superposition method uses two independent (global and local) finite element meshes and the concept of superposing the local mesh arbitrarily on the global continuous mesh. The crack is treated by the local mesh and the homogenized material model is considered on the global mesh. Numerical experiments for problems on biomorphic microcellular ceramic templates with porous microstructures of different materials constituents are presented.

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Kim, Tae Won. "Failure Analysis of Heterogeneous Microstructures in Ti-6Al-4V Alloy Using Probability Functions." Key Engineering Materials 297-300 (November 2005): 1852–57. http://dx.doi.org/10.4028/www.scientific.net/kem.297-300.1852.

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A stochastic approach has been presented for superplastic deformation of Ti-6Al-4V alloy, and probability functions are used to model the heterogeneous phase distributions. Experimentally observed spatial correlation functions are developed, and microstructural evolutions together with superplastic deformation behavior have been investigated by means of the probability functions. The strain-rate dependent failure strain can be correctly predicted by the model. As shown by the results the probability varies approximately linearly with separation distance, and significant deformation enhanced probability changes occur during the process. Since an initial microstructure is the most crucial factor that determines the properties of final microstructure, Monte Carlo simulation has been used coupled with the probability functions for the reconstruction of microstructures. By imposing the precisely optimized distributions of phase on the test specimens, therefore finite element implementation shows better agreement with experimental data of the failure strain.

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Campbell, A., P. Murray, E. Yakushina, A. Borocco, P. Dokladal, E. Decencière, W. Ion, and S. Marshall. "Automated analysis of platelet microstructures using a feature length orientation space." Journal of Materials Science 57, no. 2 (January 2022): 1448–61. http://dx.doi.org/10.1007/s10853-021-06630-6.

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AbstractThe ability to measure elongated structures such as platelets and colonies, is an important step in the microstructural analysis of many materials. Widely used techniques and standards require extensive manual interaction making them slow, laborious, difficult to repeat and prone to human error. Automated approaches have been proposed but often fail when analysing complex microstructures. This paper addresses these challenges by proposing a new, automated image analysis technique, to reliably assess platelet microstructure. Tools from Mathematical Morphology are designed to probe the image and map the response onto a new feature-length orientation space (FLOS). This enables automated measurement of key microstructural features such as platelet width, orientation, globular volume fraction, and colony size. The method has a wide field of view, low dependency on input parameters, and does not require prior thresholding, common in other automated analysis techniques. Multiple datasets of complex Titanium alloys were used to evaluate the new techniques which are shown to match measurements from expert materials scientists using recognized standards, while drastically reducing measurement time and ensuring repeatability. The per-pixel measurement style of the technique also allows for the generation of useful colourmaps, that aid further analysis and provide evidence to increase user confidence in the quantitative measurements.

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Miranda-Hernández, José G., Enrique Rocha-Rangel, and Sebastián Díaz de la Torre. "Synthesis, microstructural analysis and mechanical properties of alumina-matrix cermets." Epitoanyag - Journal of Silicate Based and Composite Materials 62, no. 1 (2010): 2–5. http://dx.doi.org/10.14382/epitoanyag-jsbcm.2010.1.

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Wang, Jia Ding, Quan Ren, Tian Feng Gu, and Yuan Jun Xu. "The Text Analysis on the Relationship between Slide-Zone Loess Porosity Microstructure and Dynamic Parameters." Applied Mechanics and Materials 638-640 (September 2014): 633–38. http://dx.doi.org/10.4028/www.scientific.net/amm.638-640.633.

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Through analyzing slide-zone loess porosity microstructure and quantitative analysis, the article can obtain the relation between variational characteristics of slide-zone loess porosity micro-structure and dynamic stress. Experimental results show that slide-zone loess microstructural parameters with load increasing appears a certain laws, and we can use simple linear equation to stand for the relation between porosity quantity or porosity area or porosity morphology ratio and dynamic stress. There is a negative correlation between porosity quantity and dynamic stress, but to other microstructural parameters and dynamic stress, it is a positive correlation. All of these laws are closely related to porosity transformation that forming under axial dynamic stress. It is worth mentioning that porosity fractal dimension with increasing dynamic stress increases, appearing linear correlation. When the confidence coefficient is 0.05, their correlation is well. Synthesizing above study, there is some guiding significance for establishing loess microstructure mechanical model and soil mass microstructural mechanics.

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Ural, Nazile. "The significance of scanning electron microscopy (SEM) analysis on the microstructure of improved clay: An overview." Open Geosciences 13, no. 1 (January 1, 2021): 197–218. http://dx.doi.org/10.1515/geo-2020-0145.

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Abstract This study aims to emphasize the importance of scanning electron microscopy (SEM) in explaining the differences in the physical and mechanical behaviors of the improved clays before and after improvement. Generally, clays appear as problematic soils in the construction area. The reasons for this can be low strength, high compressibility, high level of volumetric changes, and swelling potential. The behavior of clays may not always be interpreted according to their physical and mechanical properties. In such cases, analyses are carried out according to the microstructure of the clay. Among several microstructural analyzes, SEM is very important, because the soil microstructure formed by clay particles and additives can be observed. This work discusses the studies based on the microstructural properties of the improved clay with SEM analysis. As a result of the studies carried out, it has been seen that unexplained physical or mechanical behavior can be explained by the microstructural behaviors of clay particles and additives.

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Oblitas, Jimy, Jezreel Mejia, Miguel De-la-Torre, Himer Avila-George, Lucía Seguí Gil, Luis Mayor López, Albert Ibarz, and Wilson Castro. "Classification of the Microstructural Elements of the Vegetal Tissue of the Pumpkin (Cucurbita pepo L.) Using Convolutional Neural Networks." Applied Sciences 11, no. 4 (February 10, 2021): 1581. http://dx.doi.org/10.3390/app11041581.

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Although knowledge of the microstructure of food of vegetal origin helps us to understand the behavior of food materials, the variability in the microstructural elements complicates this analysis. In this regard, the construction of learning models that represent the actual microstructures of the tissue is important to extract relevant information and advance in the comprehension of such behavior. Consequently, the objective of this research is to compare two machine learning techniques—Convolutional Neural Networks (CNN) and Radial Basis Neural Networks (RBNN)—when used to enhance its microstructural analysis. Two main contributions can be highlighted from this research. First, a method is proposed to automatically analyze the microstructural elements of vegetal tissue; and second, a comparison was conducted to select a classifier to discriminate between tissue structures. For the comparison, a database of microstructural elements images was obtained from pumpkin (Cucurbita pepo L.) micrographs. Two classifiers were implemented using CNN and RBNN, and statistical performance metrics were computed using a 5-fold cross-validation scheme. This process was repeated one hundred times with a random selection of images in each repetition. The comparison showed that the classifiers based on CNN produced a better fit, obtaining F1–score average of 89.42% in front of 83.83% for RBNN. In this study, the performance of classifiers based on CNN was significantly higher compared to those based on RBNN in the discrimination of microstructural elements of vegetable foods.

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Timotijević, Milica, Olivera Erić-Cekić, Dragan Rajnović, and Petar Janatović. "Microstructural analysis of a HP 40Nb alloy aged." Engineering Today 1, no. 3 (2022): 41–47. http://dx.doi.org/10.5937/engtoday2203041t.

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In this paper, the change in the microstructure of the centrifugally cast heat-resistant alloys of HP40 Nb after exposure to 0.5h and 2h of ageing times at 1123K and 1323K were investigated. The microstructures of the as-received alloy and aged conditions were examined using light microscopy (LM) and scanning electron microscopy (SEM) equipped with an energy dispersive spectroscopy (EDS). The chemical composition of various phases and precipitates observed in the aged sample microstructure was characterized by the means of scanning electron microscopy SEM via backscattered electron (BSE). The present results indicate that ageing enhanced the occurrence of different phenomena such as the transformation of primary M7C3 to M23C6 carbides and precipitation of secondary M23C6 carbides. It can be summarized that the present phases and the morphology of secondary carbides in the microstructure of aging results in higher values of hardness.

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Hilgendorff, Philipp Malte, Andrei Grigorescu, Martina Zimmermann, Claus Peter Fritzen, and Hans Jürgen Christ. "Simulation of the Interaction of Plastic Deformation in Shear Bands with Deformation-Induced Martensitic Phase Transformation in the VHCF Regime." Key Engineering Materials 664 (September 2015): 314–25. http://dx.doi.org/10.4028/www.scientific.net/kem.664.314.

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The experimental observation of the microstructural deformation behavior of a metastable austenitic stainless steel tested at the real VHCF limit indicates that plastic deformation is localized and accumulated in shear bands and martensite formation occurs at grain boundaries and intersecting shear bands. Based on these observations a microstructure-sensitive model is proposed that accounts for the accumulation of plastic deformation in shear bands (allowing irreversible plastic sliding deformation) and considers nucleation and growth of deformation-induced martensite at intersecting shear bands. The model is numerically solved using the two-dimensional (2-D) boundary element method. By using this method, real simulated 2-D microstructures can be reproduced and the microstructural deformation behavior can be investigated within the microstructural morphology. Results show that simulation of shear band evolution is in good agreement with experimental observations and that prediction of sites of deformation-induced martensite formation is possible in many cases. The analysis of simulated shear stresses in most critical slip systems under the influence of plastic deformation due to microstructural changes contributes to a better understanding of the interaction of plastic deformation in shear bands with deformation-induced martensitic phase transformation in the VHCF regime.

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Ma, Yun Dong, and Shuang Liang. "Tunnel Lining Microstructure and Mechanical Properties of Evolutionary Analysis." Applied Mechanics and Materials 580-583 (July 2014): 1168–73. http://dx.doi.org/10.4028/www.scientific.net/amm.580-583.1168.

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For the tunnel lining microstructure, mechanical properties evolve analyzed. This paper have established and meshed microstructural model and got the situation under its force structure loads, the cracking strain as a criterion for its application fracture criterion to get a good cracking and expansion of the tunnel lining meso model. The results of the case under the macrostructure of the model compared with the microstructure results can get the adventage of the microstructure in using tunnel lining.

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Trzciński, Jerzy, and Emilia Wójcik. "Application of microstructure classification for the assessment of the variability of geological-engineering and pore space properties in clay soils." Open Geosciences 11, no. 1 (June 12, 2019): 236–48. http://dx.doi.org/10.1515/geo-2019-0019.

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Abstract The performed investigations were focused on analysing the variability of geological-engineering properties in clay soils from central-eastern Europe with regard to microstructures. Thirty-nine soils differing in origin, lithology and microstructure type were selected for analysis. Results of studies on lithological and physical and mechanical parameters were analysed, coupled with quantitative microstructural parameters based on microstructure images. The relationships between lithological, physical and mechanical and pore space parameters were determined with regard to microstructure types. Sediment origin and diagenesis, and soil microstructure and pore space parameters had influence on the geological-engineering properties. Such approach allows for predicting engineering parameters based on soil microstructure types and their pore space parameters.

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Galant, Grzegorz, Jan Dulęba, Sebastian Toczek, Beata Dubiel, and Aleksandra Czyrska-Filemonowicz. "Quantitative Microstructural Analysis of Thermal Barrier Coatings Deposited on Inconel 625." Solid State Phenomena 197 (February 2013): 70–76. http://dx.doi.org/10.4028/www.scientific.net/ssp.197.70.

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The aim of the present work was to determine the influence of air plasma spraying (APS) parameters on the microstructure of thermal barrier coatings (TBC) consisting on NiCoCrAlY bond coat and yttria - stabilized zirconia (YSZ) top coat. The scope of the investigation involved macroscopic observation and microstructural analysis by means of light microscopy (LM) and scanning electron microscopy (SEM). For the varied parameters of deposition process quantitative analysis of coatings thickness, porosity, oxide inclusions, metallic inclusions, globular inclusions and cracks were performed. The results of quantitative analysis allowed to establish which APS conditions influence the particular microstructural parameters of TBC coatings.

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Li, Nan, Jian Guo Lin, and Trevor A. Dean. "Development of Unified Viscoplastic-Damage Model for Crashworthiness Analysis of Boron Steel Safety Components with Tailored Microstructures." Applied Mechanics and Materials 784 (August 2015): 427–34. http://dx.doi.org/10.4028/www.scientific.net/amm.784.427.

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Hot stamped boron steel panels with tailored properties are popular as car safety components for maximised energy absorption. In this study, dynamic and quasi-static tensile tests (strain rate: 0.001/s – 500/s) combined with microstructural observation were carried out to study the mechanical properties of press hardened boron steel with various microstructures (martensite volume fraction: 0 – 100%) at room temperature. Based on the test results, a physically-based unified viscoplastic-damage constitutive model has been developed and determined, which takes the volume fraction of martensite into account. Thus the crashworthiness and failure mode of boron steel parts having graded microstructure distributions can be described through a single set of equations.

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Mishnaevsky, Leon. "Computational Analysis of the Effects of Microstructures on Damage and Fracture in Heterogeneous Materials." Key Engineering Materials 306-308 (March 2006): 489–94. http://dx.doi.org/10.4028/www.scientific.net/kem.306-308.489.

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3D FE (finite element) simulations of the deformation and damage evolution of particle reinforced composites are carried out for different microstructures of the composites. Several new methods and programs for the automatic reconstruction of 3D microstructures of composites on the basis of the geometrical description of microstructures as well as on the basis of the voxel array data have been developed and tested. Different methods of reconstruction and generation of finite element models of 3D microstructures of composite materials (geometry-based and voxel array based) are discussed and compared. It was shown that FE analyses of the elasto-plastic deformation and damage of composite materials using the microstructural models of materials generated with these methods yield very close results. Numerical testing of composites with random, regular, clustered and gradient arrangements of spherical particles is carried out. The fraction of failed particles and the tensile stress-strain curves were determined numerically for each of the microstructures. It was found that the rate of damage growth as well as the critical applied strain, at which the damage growth in particles begins, depend on the particle arrangement, and increase in the following order: gradient < random < regular < clustered microstructure.

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Liu, Lishuai, Peng Wu, Yanxun Xiang, and Fu-Zhen Xuan. "Autonomous characterization of grain size distribution using nonlinear Lamb waves based on deep learning." Journal of the Acoustical Society of America 152, no. 3 (September 2022): 1913–21. http://dx.doi.org/10.1121/10.0014289.

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Characterization of grain microstructures of metallic materials is crucial to materials science and engineering applications. Unfortunately, the universal electron microscopic methodologies can only capture two-dimensional local observations of the microstructures in a time-consuming destructive way. In this regard, the nonlinear ultrasonic technique shows the potential for efficient and nondestructive microstructure characterization due to its high sensitivity to microstructural features of materials, but is hindered by the ill-posed inverse problem for multiparameter estimation induced by the incomplete understanding of the complicated nonlinear mechanical interaction mechanism. We propose an explainable nonlinearity-aware multilevel wavelet decomposition-multichannel one-dimensional convolutional neural network to hierarchically extracts multilevel time-frequency features of the acoustic nonlinearity and automatically model latent nonlinear dynamics directly from the nonlinear ultrasonic responses. The results demonstrate that the proposed approach establishes the complex mapping between acoustic nonlinearity and microstructural features, thereby determining the lognormal distribution of grain size in metallic materials rather than only average grain size. In the meantime, the integration of the designed nonlinearity-aware network and the quantitative analysis of component importance provides an acceptable physical explainability of the deep learning approach for the nonlinear ultrasonic technique. Our study shows the promise of this technique for real-time in situ evaluation of microstructural evolution in various applications.

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Kulosa, Matthias, Matthias Neumann, Martin Boeff, Gerd Gaiselmann, Volker Schmidt, and Alexander Hartmaier. "A Study on Microstructural Parameters for the Characterization of Granular Porous Ceramics Using a Combination of Stochastic and Mechanical Modeling." International Journal of Applied Mechanics 09, no. 05 (July 2017): 1750069. http://dx.doi.org/10.1142/s1758825117500697.

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To correlate the mechanical properties of granular porous materials with their microstructure, typically porosity is being considered as the dominant parameter. In this work, we suggest the average coordination number, i.e., the average number of connections that each grain of the porous material has to its neighboring grains, as additional — and possibly even more fundamental — microstructural parameter. In this work, a combination of stochastic and mechanical modeling is applied to study microstructural influences on the elastic properties of porous ceramics. This is accomplished by generating quasi-two-dimensional (2D) and fully three-dimensional (3D) representative volume elements (RVEs) with tailored microstructural features by a parametric stochastic microstructure model. In the next step, the elastic properties of the RVEs are characterized by finite element analysis. The results reveal that the average coordination number exhibits a very strong correlation with the Young’s modulus of the material in both 2D and 3D RVEs. Moreover, it is seen that quasi-2D RVEs with the same average coordination number, but largely different porosities, only differ very slightly in their elastic properties such that the correlation is almost unique. This finding is substantiated and discussed in terms of the load distribution in microstructures with different porosities and average coordination numbers.

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Dong, Qin, Zhong Wei Yin, Hu Lin Li, Yang Mao, and Geng Yuan Gao. "3D Reconstruction of Microstructure for Centrifugal Casting Babbitt Lining of Bimetallic Bearing Based on Mimics." Key Engineering Materials 841 (May 2020): 94–98. http://dx.doi.org/10.4028/www.scientific.net/kem.841.94.

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Babbitt alloys are the most commonly used bearing materials for low speed diesel engines due to their excellent attributes. An understanding of microstructures in these alloys is important, especially quantifying microstructure in 3D. In this study, we used serial sectioning technique to reconstruct 3D microstructure of tin-based Babbitt lining of bimetallic bearing made by centrifugal casting based on medical software Mimics. The morphologies and volume fraction of hard phase particles and α-Sn matrix were obtained. The volume fraction of the reconstructed microstructures was verified by the area fraction of the metallographic sections, which proved a higher reliability of 3D reconstruction. The results of 3D microstructural characterization and analysis will enable a comprehensive understanding the structure–property relationships of these materials.

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Cheepu, Muralimohan, D. Venkateswarlu, P. Nageswara Rao, V. Muthupandi, K. Sivaprasad, and Woo Seong Che. "Microstructure Characterization of Superalloy 718 during Dissimilar Rotary Friction Welding." Materials Science Forum 969 (August 2019): 211–17. http://dx.doi.org/10.4028/www.scientific.net/msf.969.211.

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In the present study, dissimilar friction welding between super alloy 718 and carbon steel friction welded to evaluate the formation of microstructure in the weld interface and in superalloy 718. The temperature during friction welding at weld interface was recorded to determine the temperature effect on the microstructural changes on alloy 718 side. The finite element modeling of weld interface temperature, deformation and stresses were evaluated and validated with the experimental results. The microstructural observation along with the weld interface and adjacent regions are studied. The effect of friction welding on superalloy weld interface and microstructural formation were investigated under electron backscattered diffraction analysis to evaluate the grain size measurements. The effect of thermomechanical action on the microstructure was evaluated by texture analysis.

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Darras, Bassil M., M. A. Omar, and Marwan K. Khraisheh. "Experimental Thermal Analysis of Friction Stir Processing." Materials Science Forum 539-543 (March 2007): 3801–6. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.3801.

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Despite the large number of studies that are being conducted to advance the friction stir processing (FSP) technology, the effects of FSP on various mechanical and microstructural properties are still in need for further investigations. In addition, correlations between FSP parameters, mechanical properties and microstructural characteristics are not yet well understood. Accurate correlations are needed for successful modeling and process optimization. It is established that the temperature generated during FSP plays an important role in determining the microstructure and properties of the processed sheet and defining the tool life. Process parameters must be carefully chosen to allow the generation of enough heat to soften the material while limiting significant grain growth. Accurate measurement of the temperature distributions during processing are essential to understand the complicated deformation and associated mechanisms and to allow for effective process optimization. In this work, a dual-band thermography approach is used to measure the temperature distributions of AA5052 sheet during FSP. The setup utilizes two infrared detectors, to neutralize the emissivity and the facial effects, with 30 Hz acquisition rate. The variation of temperature with process parameters and their correlation to the resulting microstructure are discussed.

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Buzoverya, M. E., Yu P. Shcherbak, I. V. Shishpor, and Yu P. Potekhina. "Microstructural analysis of biological fluids." Technical Physics 57, no. 7 (July 2012): 1019–24. http://dx.doi.org/10.1134/s1063784212070079.

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Bouchon, Pedro, and Jose M. Aguilera. "Microstructural analysis of frying potatoes." International Journal of Food Science and Technology 36, no. 6 (August 2001): 669–76. http://dx.doi.org/10.1046/j.1365-2621.2001.00499.x.

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42

Fang, Herbert H. P., and H. K. Chui. "Microstructural analysis of anaerobic granules." Biotechnology Techniques 7, no. 7 (July 1993): 407–10. http://dx.doi.org/10.1007/bf00151874.

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Calisti, V., A. Lebée, A. A. Novotny, and J. Sokolowski. "Sensitivity of the Second Order Homogenized Elasticity Tensor to Topological Microstructural Changes." Journal of Elasticity 144, no. 2 (May 2021): 141–67. http://dx.doi.org/10.1007/s10659-021-09836-6.

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AbstractThe multiscale elasticity model of solids with singular geometrical perturbations of microstructure is considered for the purposes, e.g., of optimum design. The homogenized linear elasticity tensors of first and second orders are considered in the framework of periodic Sobolev spaces. In particular, the sensitivity analysis of second order homogenized elasticity tensor to topological microstructural changes is performed. The derivation of the proposed sensitivities relies on the concept of topological derivative applied within a multiscale constitutive model. The microstructure is topologically perturbed by the nucleation of a small circular inclusion that allows for deriving the sensitivity in its closed form with the help of appropriate adjoint states. The resulting topological derivative is given by a sixth order tensor field over the microstructural domain, which measures how the second order homogenized elasticity tensor changes when a small circular inclusion is introduced at the microscopic level. As a result, the topological derivatives of functionals for multiscale models can be obtained and used in numerical methods of shape and topology optimization of microstructures, including synthesis and optimal design of metamaterials by taking into account the second order mechanical effects. The analysis is performed in two spatial dimensions however the results are valid in three spatial dimensions as well.

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Montavon, G., C. Coddet, C. C. Berndt, and S. H. Leigh. "Microstructural Index to Quantify Thermal Spray Deposit Microstructures Using Image Analysis." Journal of Thermal Spray Technology 7, no. 2 (June 1, 1998): 229–41. http://dx.doi.org/10.1361/105996398770350972.

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Strzelecki, Piotr Jan, Anna Świerczewska, Katarzyna Kopczewska, Adam Fheed, Jacek Tarasiuk, and Sebastian Wroński. "Decoding Rocks: An Assessment of Geomaterial Microstructure Using X-ray Microtomography, Image Analysis and Multivariate Statistics." Materials 14, no. 12 (June 13, 2021): 3266. http://dx.doi.org/10.3390/ma14123266.

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An understanding of the microstructure of geomaterials such as rocks is fundamental in the evaluation of their functional properties, as well as the decryption of their geological history. We present a semi-automated statistical protocol for a complex 3D characterization of the microstructure of granular materials, including the clustering of grains and a description of their chemical composition, size, shape, and spatial properties with 44 unique parameters. The approach consists of an X-ray microtomographic image processing procedure, followed by measurements using image analysis and statistical multivariate analysis of its results utilizing freeware and widely available software. The statistical approach proposed was tested out on a sandstone sample with hidden and localized deformational microstructures. The grains were clustered into distinctive groups covering different compositional and geometrical features of the sample’s granular framework. The grains are pervasively and evenly distributed within the analysed sample. The spatial arrangement of grains in particular clusters is well organized and shows a directional trend referring to both microstructures. The methodological approach can be applied to any other rock type and enables the tracking of microstructural trends in grains arrangement.

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Anghelina, Florina Violeta, Vasile Bratu, Elena Valentina Stoian, and Ileana Nicoleta Popescu. "Microstructural Investigation of Aluminum Alloys Type "2024" for the Aviation Industry." Advanced Materials Research 1114 (July 2015): 62–67. http://dx.doi.org/10.4028/www.scientific.net/amr.1114.62.

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This paper presents experimental results revealed on the samples type 2024 aluminum alloy used in aeronautics. The results of microstructural and compositional investigations presented in this paper were performed on samples taken from 2024 Al alloy samples produced by ALRO Slatina. The main objective of the investigation is the conformity assessment of alloys in terms of chemical composition with the specifications type of aviation [SAE AMS 47N, EN 515, etc]. It also aims microstructural conformity assessment in terms of the grain and the hardening effects by natural or artificial aging applied by the manufacturer. Adequate characterization of 2024 aluminum alloys type was achieved by combined investigations: (i) Wet Chemical Analysis, (ii) Spectrochemical Analysis and (iii) Electron Microscopy. The main conclusion that emerges from the investigations carried out on aluminum samples revealed that: (a) alloys fits in terms of composition with the standard specification for 2024, in all cases; (b) microstructure vary in fineness of grain, but meets the requirements of aviation rules; the investigated microstructures have been appreciated as adequate of aluminum alloys type "2024".

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Kim, Vladimir A., Boris Ya Mokritskii, and A. V. Morozova. "Multifractal Analysis of Microstructures after Laser Treatment of Steels." Solid State Phenomena 299 (January 2020): 926–32. http://dx.doi.org/10.4028/www.scientific.net/ssp.299.926.

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The superficial microstructure, received by laser processing, is characterized by a high density of defects of a crystal structure and incompleteness of thermal phase and structural transformations. The degree of a neravnovesnost of such a structure can be estimated by means of multifractal ranges. As a measure for calculation of multifractals, it is possible to use any quantitative structural index, in particular, the area of microstructural objects, their perimeter and density of borders. The most informative is density of borders, which considers the area and perimeter of structural object. Microstructures of stainless steel 12kh18n10t in an initial state, after laser processing and a local laser alloying by hard-alloy powder from BK8 were investigated. Calculations of complex indicators of the structural organization of material, which showed, are executed on the basis of the multifratalnykh of ranges, that laser processing leads to, increase of orderliness and frequency. It indicates high degree of a neravnovesnost with which increase hardening increases.

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Ok, Myoung Ryul, Eun Young Kang, Ji Hye Kim, Young Su Ji, Chang Woo Lee, Young Joo Oh, and Kyung Tae Hong. "Analysis on the Microstructure of Ceramic Coating Layer Fabricated by Plasma Electrolytic Oxidation." Materials Science Forum 539-543 (March 2007): 1258–63. http://dx.doi.org/10.4028/www.scientific.net/msf.539-543.1258.

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Plasma electrolytic oxidation (PEO) has drawn attention and been studied intensively all through the world. The thick ceramic coatings fabricated by the technique exhibit excellent properties, including hardness and wear resistance, thermal and electrical insulation, and corrosion resistance, due to the characteristic phase composition and microstructure of the coating layers. However, most of the studies have dealt with manufacturing process itself and the apparent properties of coating layers and researches on the microstructural basis including transmission electron microscopy analysis are limited so far. In this investigation, a basic approach to PEO process was tried, adapting time-potential behavior analysis under constant current mode (galvanostatic) oxidation, and microstructural analysis on the coating structure, including X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The time-potential behavior analysis under constant current DC was carried out, and the resultant evolution of the microstructure was characterized..

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Dehghanpour, Hamid Reza, Parviz Parvin, Seyedeh Zahra Mortazavi, Ali Reyhani, Amin Chegenizadeh, and Mohammadreza Aghaei. "Analysis of Surface Texturing of Silicon with Surface Regular Microstructure Using C Method." Energies 15, no. 20 (October 13, 2022): 7540. http://dx.doi.org/10.3390/en15207540.

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Silicon, as the most abundant element in the earth’s crust and the most common material used in electronic and optical equipment, has attracted the attention of many individuals to change the properties of this material, improving its electronic and optical properties. One of these efforts relies on the reduction of surface reflection by making use of different methods. However, among them, the use of lasers in creating surface microstructures has been of special importance because there is no need for masks and other additional materials. In this work, a theoretical method is utilized to analyze these textures with the theorem of diffraction grating on a micrometer scale. The surface reflection of the microstructure created by excimer laser exposure on a silicon surface is simulated. The theoretical Coordinate transformation method (C method) gives out notable results against the experimental records by approximating triangular and trapezoidal microstructures. The model is useful for predicting the reflective response of the modified microstructural morphology. One of the main applications is the texturing of the solar cell front faces to enhance their efficiency, mainly due to photon trapping.

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Weiland, H., and D. P. Field. "Automatic analysis of Kikuchi diffraction patterns." Proceedings, annual meeting, Electron Microscopy Society of America 52 (1994): 900–901. http://dx.doi.org/10.1017/s0424820100172231.

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Recent advances in the automatic indexing of backscatter Kikuchi diffraction patterns on the scanning electron microscope (SEM) has resulted in the development of a new type of microscopy. The ability to obtain statistically relevant information on the spatial distribution of crystallite orientations is giving rise to new insight into polycrystalline microstructures and their relation to materials properties. A limitation of the technique in the SEM is that the spatial resolution of the measurement is restricted by the relatively large size of the electron beam in relation to various microstructural features. Typically the spatial resolution in the SEM is limited to about half a micron or greater. Heavily worked structures exhibit microstructural features much finer than this and require resolution on the order of nanometers for accurate characterization. Transmission electron microscope (TEM) techniques offer sufficient resolution to investigate heavily worked crystalline materials.Crystal lattice orientation determination from Kikuchi diffraction patterns in the TEM (Figure 1) requires knowledge of the relative positions of at least three non-parallel Kikuchi line pairs in relation to the crystallite and the electron beam.

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Journal articles on the topic 'Microstructural analysis'

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