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• Experimental investigation of wetting behaviour in Cu-In alloy is carried out. • Studies based on scanning electron microscopy and energy dispersive spectroscopy are carried out to identify wetting behaviour. • Indium seems to considerably affect the wetting transition at triple grain junction. This work investigates Cu-In alloy at 15% indium for wetting behaviour after heat treatment at 800 ⁰C. The system is observed to show wetting behaviour at triple junction (grain junction) through Scanning electron microscope imaging. It is observed in energy dispersive spectroscopy that after annealing, increased segregation of indium near triple junction is responsible for this wetting behaviour. The current work is critical to development of advanced materials with better mechanical characteristics at high temperatures. [ABSTRACT FROM AUTHOR]

• The present paper mainly investigates the damping behaviour of AA6061. • Grain refinement was studied with the help of electron back scattered diffraction. • Intermetallic behaviour was studied under the scanning electron microscope. • Damping behaviour is correlated with grain size and intermetallic behaviour. The effect of brass interlayer and water cooling on the damping behavior of friction stir welded AA6061 was investigated in the present work. The results revealed that weld samples showed better damping capacity than base metal attributed to the grain refinement. Moreover, the damping capacity of weld with the addition of interlayer is enhanced due to more grain refinement, formation of hard intermetallics, and high inherent damping capacity of brass. The reduced intermetallics and formation of smooth interface obtained for water-cooled weld attributed to the faster cooling rate improved the mobility of grain boundaries which enhanced the damping capacity than natural cooling. The water-cooled weld with interlayer showed better damping at high temperatures than other weld joints due to the increased grain boundary area. [ABSTRACT FROM AUTHOR]

To improve corrosion resistance and enhance biocompatibility of magnesium alloy, cathodic plasma electrolysis (CPE), a liquid phase plasma technique, was used to fabricate zirconia (ZrO2) coatings onto WE43 magnesium alloy substrate. Surface morphology and phase composition of the coatings on magnesium alloy substrates were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD), respectively. The potentiodynamic polarization test in simulated body fluid (SBF) indicated that corrosion resistance of magnesium alloy was significantly improved by this CPE treatment. The results of cytocompatibility including osteoblasts adhesion and viability suggested that surface modification of magnesium alloy with ZrO2 coating fo'rmed via CPE technique is beneficial for cell proliferation and differentiation. The approach presented here should be an attractive way for surface modification of magnesium-based implants to improve anticorrosion and bone osseointegration. [ABSTRACT FROM AUTHOR]

[Display omitted] • Graded NiCoW coating was synthesized by one step, galvanostatic, DC electrodeposition. • Graded NiCoW coatings possess composition and structure varying crossing thickness. • Induced co-deposition mechanism of graded NiCoW coatings has been elucidated. In this paper, a novel method for synthesis of functionally graded alloy coatings by using induced co-deposition has been proposed. The graded NiCoW alloy coatings were synthesized by one step, galvanostatic, direct current electrodeposition from a sulphate-citrate electrolyte. Scanning electron microscope, energy dispersive spectroscopy and X-ray diffractometer were applied to characterize the as-deposited coatings, which possess the composition and structure gradually varying crossing the coating thickness. During the electrodeposition, the competition between the formation of Ni complexes and Co complexes as well as the competition between induced deposition of W and direct deposition of Ni, are responsible for the formation of graded NiCoW coatings. This easy synthesis method by using induced electrodeposition should be a promising route for the preparation of functionally graded alloy materials. [ABSTRACT FROM AUTHOR]

• The fatigue behavior of AA2014 alloy is investigated. • The fracture features of different regions were examined under Scanning electron Microscope. • The fatigue behavior of each sample is correlated with microstructural features. The present investigation studies the actual fatigue crack growth behavior of AA2014 alloy processed using multi-pass overlapping friction stir processing. The results revealed that friction stir processed samples sustained a large number of fatigue cycles than base metal due to the various microstructural aspects in the processed zone. The fractured surface of fatigue samples revealed the presence of ridges and plateaus in the Stage-I crack propagation region and dimples and striations in the Stage-II crack propagation region. [ABSTRACT FROM AUTHOR]

• The effects of Cu or Zn on the fluidity of A357 alloy were investigated. • With increase of Cu or Zn content, the fluidity of A357 alloy decreased. • With increase of Cu or Zn, the solidification temperature range increased. • The coarse grain is not the main reason for the fluidity to deteriorate. Excellent fluidity is an essential condition for Al-Si-Mg alloy (like A357) to make large thin-walled and complex structure castings, but t here is no research about the effects of Cu or Zn on the fluidity of Al-Si-Mg alloys. Under sand casting conditions, the effects of Cu or Zn on the fluidity of A357 were investigated through spiral fluidity resin sand molds, DSC, polarizing microscope and SEM. The results showed that with increase of Cu or Zn content, the solidification temperature range (T) of A357 alloy increased, and the fluidity decreased. With Cu or Zn addition, the grain size of A357 alloy increased, but the coarse grain is not the main reason for the fluidity to deteriorate. [ABSTRACT FROM AUTHOR]

• Basal and prismatic slips are the dominant deformation modes of α ′ phase in TA6V. • CRSS values of alpha phase can well describe the deformation behavior of the α ′ phase in TA6V. • A modified Schmid analysis can be used to determine the CRSS values of the α ′ phase. Plastic deformation of α ′ martensite phase in Ti-6Al-4V alloy is investigated by performing tensile tests in a Scanning Electron Microscope (SEM). Electron Backscatter Diffraction (EBSD) analysis is used to determine the slip modes activated in α ′ martensite depending on the crystallographic orientation of the laths. As in the α phase, mostly basal and prismatic slip modes are identified. The weighted Schmid analysis applied using the critical resolved shear stress (CRSS) values of the α phase performs well in the description of the behavior of the α ′ phase. [ABSTRACT FROM AUTHOR]

• Nano-width martensite plates in a Ni 50 Ti 50 alloy are indexed successfully by off-axis SEM-TKD. • B19′ martensite variants are identified without the reference of retained austenite. • Equivalent variant rotations are used to facilitate unambiguous interpretation. • A complete list of source martensite to target martensite pairs is formulated. Nano-width martensite plates in a fully martensitic Ni 50 Ti 50 alloy are indexed successfully by using the off-axis transmission Kikuchi diffraction in scanning electron microscope (i.e., SEM-based TKD). The data obtained by SEM-TKD are effectively interpreted using an improved approach based on the framework of the theoretical groupoid structure method, where the equivalent variants transformed from the monoclinic variants are introduced to calculate all theoretical axis/angle pairs of rotation, and to formulate a complete list of source martensite to target martensite pairs. Consequently, B19′ monoclinic martensite variants in NiTi alloys are identified unambiguously, by using numerical comparison between the experimental and theoretical rotation components, without the reference of retained parent phase. [ABSTRACT FROM AUTHOR]

• The 3D microstructure of laser remelted Be-Al alloy was reconstructed by using FIB/SEM. • A significantly refined structure of the Be-Al alloy can be obtained through laser remelting. • The microstructure can be customized by optimizing the processing parameters. In this study, the beryllium-aluminum (Be-Al) alloy was processed using laser remelting (LR), and the microstructure was investigated using a 3D reconstruction technique. Focused ion beam/scanning electron microscope (FIB/SEM) reconstruction reveals that the microstructure consisted of a continuous network of Al phases wrapping the columnar Be phase. The columnar Be phases grow from the substrate towards the remelting zone and are oriented in different directions at the top of the molten pool. The gradient solidification rate explains well the gradual size reduction of the Be phase from the bottom to the top of the molten pool. These results reveal that LR is an effective method and that microstructures can be customized by optimizing the processing parameters. [ABSTRACT FROM AUTHOR]