In order to achieve a light and corrosion-resistant structural material, Al-coated Mg alloy sheet has been fabricated by hot extrusion followed by hot rolling. The sheet was successfully rolled at 623 K without any breaking of the Al coating layer, and the sheet exhibited an excellent corrosion resistance. The mechanical properties have been investigated by tensile tests at various temperatures and strain rates. At room temperature, the stress value drops immediately after reaching the maximum, while the value decreases as the temperature increases and the strain rate decreases. It has been demonstrated that the sheet exhibits elongation of 707 % at 573 K at 1.0×10^-3 s^-1 when tensile-tested in the rolling direction. After the elongation, the Al coating layer remained on the Mg alloy substrate. No cracks or debonding were observed at interfaces of Mg alloy/Al₃Mg₂ and Al₃Mg₂/Al.

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A sub-micron-sized metal particle has been used as a jointing material between a semiconductor device and a circuit electrode because of its low-temperature sintering characteristic. In this study, we have investigated a behavior of particles during heating using the molecular dynamics (MD) simulation, and we analyzed the driving force of low temperature sintering characteristic of particles. The Langevin equation and the Finnis-Sinclair potential were used on solving the equation. An Iron particles with a diameter of around 240 Å were heated at temperatures above/below the melting point (T_m) for the estimation of diffusion coefficient. The average diffusion coefficient near the center of the particle was 10^-5 cm²/sec at above T_m and was 10^-8-10^-9 cm²/sec at below T_m. On the other hand, the average diffusion coefficient at the outer layer of a particle becomes two or three orders in magnitude bigger than the center of the particle. It is conceivable that an enhanced sintering of nano-particles at low temperature is due to the high diffusion coefficient near the surface.

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