Based on 15 diffusion couples located in face centered cubic single-phase region of ternary Ni–Al–Mo system, high-throughput determination of composition-dependent interdiffusivity matrices at 1273, 1373, and 1473 K was performed by using the recently developed numerical inverse method. The determined main interdiffusivities over the investigated composition and temperature ranges are all positive, and $\tilde D_{{\rm{AlAl}}}^{{\rm{Ni}}}$ is generally larger than $\tilde D_{{\rm{MoMo}}}^{{\rm{Ni}}}$ . Moreover, $\tilde D_{{\rm{AlAl}}}^{{\rm{Ni}}}$ generally increases with concentration of Al, while $\tilde D_{{\rm{MoMo}}}^{{\rm{Ni}}}$ increases with concentrations of both Al and Mo. In contrast, the cross interdiffusivities can be either positive or negative. Average relative errors of $\tilde D_{{\rm{AlAl}}}^{{\rm{Ni}}}$ , $\tilde D_{{\rm{AlMo}}}^{{\rm{Ni}}}$ , $\tilde D_{{\rm{MoAl}}}^{{\rm{Ni}}}$ , and $\tilde D_{{\rm{MoMo}}}^{{\rm{Ni}}}$ were evaluated to be 2.4, 5.1, 16.1, and 1.7% using error propagation. Furthermore, our prediction of composition profiles and interdiffusion fluxes based on evaluated interdiffusivity matrices agrees quite well with measured data. Traditional Matano–Kirkaldy method was also applied to further verify the reliability of obtained interdiffusivities. Besides, three-dimensional planes of activation energies of main interdiffusivities were also evaluated using the Arrhenius equation.

A eutectoid carbon steel was studied at three different annealing heat treatment cycles: spheroidizing, isothermal annealing, and normalization (air cooling). The aim of this study was to determine the correlation among thermal, structural, and metallurgical properties, as a result of the annealing heat treatment. Microstructure differences were produced by the heat treatment cooling rate with significant effects on Vickers nanohardness, thermal properties, and crystallinity. It was reflected in photothermal radiometry (PTR) images as in thermal conductivity and diffusivity. The amplitude signal increased as the cooling rate increased. It means that as the cooling rate increased, crystallinity, thermal diffusivity, and conductivity decreased. The cooling rate affected the metallurgical structure directly, and consequently, the nanohardness which decreased due to the solid solution formation and decomposition of the pearlite phase. As the cooling rate increased, the nanohardness increased modifying structural properties and the steel crystallinity. As the cooling rate decreased, the crystallinity increased.

Al–(12, 20, 35 wt%)Si alloys were fabricated using powder metallurgy process involving hot pressing followed by hot extrusion. The effect of Si content on the microstructure [by scanning electron microscopy], the mechanical properties (hardness and tensile tests), and the thermal expansion behavior were studied in detail, respectively. Due to the friction between the Si phase and the matrix, as well as the diffusion of the Si atoms, the Si phase becomes a particulate shape after hot extrusion, and the size increases with increasing Si content. The mechanical strength increases, whereas, the elongation decreases with increasing the Si content from 12 to 35 wt%, which lead to a variation of the fracture mechanism from ductile to brittle failure. The coefficient of thermal expansion (CTE) decreases with increasing Si content as a result of restriction of Si on the Al matrix, and the measured CTE value is in good agreement with the Turner model below 573 K.