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Abstract: A fixed-grid source-based numerical method has been developed to simulate the diffusion-controlled growth of Cu6Sn5 and Cu3Sn intermetallic compounds (IMCs) and other many layers of IMCs. Data fittings of measured thicknesses of the IMCs to the simulated results can be further employed to determine the interdiffusion coefficients for the IMCs. Compared with the existing analytical methods, the present numerical method is not only more accurate, but also applicable to a wider range of experimental results. We report here the detailed formulation of the relevant equations, and compare and validate the present numerical method using experimental thicknesses of Cu6Sn5 and Cu3Sn IMCs from both the existing literature and the experiment of our own. The results obtained provide new insight into the interdiffusion coefficients for the Cu6Sn5 and Cu3Sn IMCs formed between Cu and Sn or Sn-based solders, or other many layers of IMCs formed in similar metal/metal systems. [Copyright &y& Elsevier]

Abstract: The phase formation and crystallization kinetics during the thermal treatment of amorphous Zr60Al15Ni25 alloy were investigated by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). By lowering the isothermal annealing temperatures, it is revealed that the crystallization of the amorphous Zr60Al15Ni25 alloy consists of a primary transformation followed by a polymorphic transformation, corresponding to the precipitations of hexagonal Zr6Al2Ni and the Zr5AlNi4 with a U3Si2-typed superstructure. The primary phase being Zr6Al2Ni rather than Zr5AlNi4 in the crystallization is because the latter has a complex structure and its formation requires the diffusion of Al and Zr atoms on a large scale. [Copyright &y& Elsevier]