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Know-how of microstructural developments during erosion of 52100 and M50 tribological steels and associated erosion resistance knowledge are required for enhancement of properties. Erosion induced microstructural features such as disintegration of martensite boundaries, normal growth of martensite lath, low angle grain boundaries, shear bands, dislocation cell structure and independent recovery islets. Fraction of low angle grain boundary was larger after oblique erosion of 52100 steel while less shear bands were produced after oblique erosion compared to normal erosion. 52100 steel also developed independent recovery islets with tight packed dislocation wall and recovered cell interior. M50 ferrite developed dislocation cell structure during normal erosion. In general normal impact has been associated with greater erosion resistance. Comparatively less ploughing has increased erosion resistance of M50 ferrite than that of M50 martensite. Normal erosion resistance of 52100 and M50 martensite has been observed to be equal.

This work describes microstructure, texture, and orientation-dependent flow behavior of Ni-16Cr and Ni-16Mo alloys in hot rolled and annealed condition. The high and low stacking fault energy values associated with Ni-16Cr and Ni-16Mo result in partial recrystallization after recovery and presence of twins in recrystallized grains, respectively. Both the alloys display two slopes in the true plastic stress–strain curves and follow Ludwigson relation, however the deformation mechanisms of both the alloys associated with two slopes are different. The low-strain regime of flow curves of the alloy Ni-16Cr is associated with uniform and finely spaced slip lines within the grains along with very small fraction of strain localization. On the other hand, a few slip lines appear to cross the grain boundaries in high-strain regime with a favorable angular deviation between adjacent grains along with large fractions of strain localization (2 to 5 deg low-angle grain boundary). On the other hand, the low-strain regime of the alloy Ni-16Mo is related to the presence of uniformly and finely spaced slip lines and small fractions of both the deformation twins as well as strain localization. The main features of high-strain regime of the alloy Ni-16Mo exhibit large volume fractions of deformation twins and strain localization along with few coarse penetrating slip lines across the grain boundaries. Sample orientation-dependent ductility of both the alloys has been explained based on dislocation storage capacity and dynamic recovery coefficient using Kock–Mecking–Estrin analysis.

The effect of 2.5 wt.% Cu addition to Ti6Al4 V alloy in regard to its structural phases and properties has been investigated. Alloying with 2.5 wt.% Cu increased the yield strength (Y.S) by 400 MPa. Solution treatment at 1283K and successive aging treatment at 773K has resulted in fine α lath structure with a very less fraction of β phase. Ageing treatment at 773K for 4 hrs and 40 hrs produced tetragonal nano Ti2Cu precipitates. The number of Ti2Cu phase increased with holding time. The precipitates were formed preferentially at the lath boundaries. The highest Yield Strength was obtained in the solution treated state without aging. Effect of strengthening by Ti2Cu was revealed in hardness measurement.

Present work describes a correlation amongst texture, in-plane anisotropy in tensile properties and yield locus in Ni–20Cr–8Fe alloy. The alloy exhibits high and moderate values of in-plane anisotropy and anisotropy index, respectively. This has been attributed to the presence of moderate overall intensity of texture as well as partially recrystallized microstructure. The tensile properties evaluated in five sample directions, namely the 0° (longitudinal or L), 22.5°, 45°, 67.5° and 90° (transverse or T) to the rolling direction, display two slopes in true plastic stress–strain curve and follow a Ludwigson relation. At low strains, sample displays the presence of annealing twins and less strain localization (1.5–3.5° boundaries) while the formation of deformation twins and high strain localization are observed in high strained region. The 67.5° orientation sample shows relatively low ductility and low work hardening exponent. This has been explained using Kock–Mecking–Estrin analysis based on higher degree of dynamic recovery/glide softening and fluctuations in work hardening rate during stage II.

Current study has been carried out to compare the development of microstructure in deformed zone of M50 bearing steel during abrasion. Three-body abrasive wear was carried out using abrasive test apparatus as per ASTM G 65-85 with applied load of 13 kg. Silica sand of dimension 200±50 μm was used as abrasives. The effect of deformed features in abrasion resistance has also been delineated. Crystallographic lath pocket oriented sheared features were observed after abrasion of martensite. Very less fractions of crystallographic sheared features were observed after abrasion of ferrite. The abrasion did not produce dislocation cell structure in ferrite. Ferrite associated just more dynamic recovery while martensite was concomitant to greater dynamic recrystallization. Major toughness enhancement by abundant sheared features and dynamic recrystallization in martensite resulted in higher abrasion resistance of martensite than ferrite.

This work describes a correlation among texture, in-plane anisotropy in tensile properties, and yield locus in Ni-based Hastelloy C-276 alloy. The alloy exhibits moderate values of in-plane anisotropy and anisotropy index, which has been attributed to the presence of moderate overall intensity of texture. The alloy displays two slopes in true plastic stress–strain curve and follows a Ludwigson relation. At low plastic strains, the sample displays the presence of annealing twins and less strain localization at grain boundaries, while the formation of deformation twins and high strain localization within the deformation twins and at the grain boundaries are observed in a high-strained region. The 45-deg and 67.5-deg orientation samples show relatively low ductility and low work-hardening exponent. This has been explained based on dislocation storage capacity and dynamic recovery coefficient using Kock–Mecking–Estrin analysis.

The strength-to-weight ratio offered by AA6XXX alloys and their enhanced mechanical properties have become crucial criteria for their use in light weight military vehicles, rockets, missiles, aircrafts, and cars, used for both defence and civil purpose. The focus of this review paper is to put together the latest knowledge available from various sources on alloy design, industrial processing, development of properties, and potential use of AA6XXX alloys. The direct chill (DC) cast AA6XXX wrought alloys which are subsequently processed by fabrication process like hot working, cold working, process annealing, and age hardening heat treatments are the foci of this review though designation section also contains the designations of cast alloys to provide the reader a broad overview on designation. World-wide accepted designations are briefly tabled along with their alloying elements. The effects of the alloying elements which are generally used for AA6XXX wrought alloys are discussed incorporating their interactions during wrought AA6XXX alloy fabrication. The significance of the alloying and also the processing to develop the certain properties and the underlying strengthening mechanisms are discussed. The frequent and versatile uses of these AA6XXX alloys for the structural applications both in defence and civil purpose are put forth.

The recovered cold rolled microstructure obtained from orientation image microstructure of Al-4%Mg-0·5%Mn alloy (AA5182 alloy) was superimposed on the grid of cellular automata based microstructure model. The Taylor factors of deformed/cold rolled orientations were considered as the driving force for recrystallization. The local development of recrystallized microstructure and texture were simulated with orientation dependent grain boundary mobility and compared with the experimental results.

AA7475 alloy was deformed up to 25% elongation in INSTRON at 788K. The grain boundary sliding due to this superplastic deformation was measured by Scanning Electron Microscope. The microstructure and texture development due to this deformation at elevated temperature was analyzed from the Orientation Image Microstructures i.e. the Electron Back Scattered Diffraction Image. The Orientation Image Microstructures revealed that superplastic deformation was associated with recovery and recrystallization in-situ process.