The effect of long-term ageing (1000, 2000, and 3000 h) at 475 °C on mechanical properties, microstructure, substructure CUSTOM 465® maraging stainless steel was studied. additional precipitation nanometric particles ?-Ni3Ti phase in partly recovered lath martensite decomposition the BCC solid solution accompanied by formation Cr-rich ?’particles were identified. fraction reverted austenite fin...

Abstract Titanium alloys are widely used in the aerospace industry, yet oxygen ingress can severely degrade mechanical properties of titanium alloy components. Atom probe tomography (APT), electron microanalysis (EPMA) and nanoindentation were to characterise oxygen-rich layer on an in-service jet engine compressor disc, manufactured from TIMETAL 834. Oxygen was quantified related changes throu...

Two solution-based methods, metallo-organic decomposition and sol–gel processes, were used to study the effects of precursor solution type on the microstructure evolution and texture development of oriented PZT films. Microstructure development and perovskite content are strongly dependent on the heating rate. Fast heating rate forms a dense fine-grained microstructure with (111) orientation. I...

This research is focused on the development of a microstructural model for phase transformation kinetics in shockwaves. It is assumed that the Hugoniot state lies in the region of metastability around an equilibrium solid-solidphase boundary, hence this model applies to transformations occurring through nucleation and growth. The modelaccounts for both homogeneous (thermally dri...

The wheel pair is a key component of the subway. Routes subway conditions are more complex, while frequent starting and braking likely to cause damage. To improve sliding tribological properties wheels, this article focused on laser-cladding technology repair wheel. Ni-based Fe-based alloy coatings were prepared. microstructure was studied by SEM, EDS, XRD, 3D optical morphology. mechanical coa...

Solid oxide fuel cells (SOFCs) are inevitably affected by the tensile stress field imposed by the rigid substrate during constrained sintering, which strongly affects microstructural evolution and flaw generation in the fabrication process and subsequent operation. In the case of sintering a composite cathode, one component acts as a continuous matrix phase while the other acts as a dispersed p...

We develop a strategy to design and evaluate high-entropy alloys (HEAs) for structural use in the transportation and energy industries. We give HEA goal properties for low (≤150 °C), medium (≤450 °C) and high (≥1,100 °C) use temperatures. A systematic design approach uses palettes of elements chosen to meet target properties of each HEA family and gives methods to build HEAs from these palettes...

A diffuse-interface model for microstructure with an arbitrary number of components and phases was developed from basic thermodynamic and kinetic principles and formalized within a variational framework. The model includes a composition gradient energy to capture solute trapping and is therefore suited for studying phenomena where the width of the interface plays an important role. Derivation o...

Two important factors affecting hot tearing – semi-solid constitutive behaviour and grain percolation – have been simulated through the use of microstructure models based on granular structures. The semi-solid model geometry is based on a modified Voronoi tessellation, and includes rounded corners to approximate an equiaxed-globular grain structure with liquid surrounding the grains. The percol...

in this research work the solid-solutions of (bi2o3)1-x (co2o3)x, [x= 0.05, 0.1] (1), (bi2o3)1-x (ho2o3) x, [x= 0.025, 0.05] (2), and (bi2o3)1-x-y (co2o3)x (ho2o3)y, [x=0.05] ; [y= 0.01, 0.02] (3) have been synthesized  using sol-gel method. the effects of transition metal oxides doping on the crystallization and phase transition of the bi2o3 were discussed by x-ray diffraction (xrd). the xrd p...