The structure and hydrogenation properties of Ti–Mg alloy synthesized by ball-milling have been investigated. In this study, α-Ti powder (HCP) was successfully transformed into β-Ti (BCC) powder by ball-milling for 216 ks. This composition was obtained to mix elemental powder of each Ti (HCP or BCC) and Mg by ball-milling with the ratio of 12.5, 25, 37.5, and 50 at% Mg. The structure and thermal stability of these samples were analyzed by means of X-ray diffractometry (XRD), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). In this results, Ti–Mg alloy with β-Ti maintained BCC phase as much as the ratio of 37.5 at% Mg, and it was the steady state until 573 K. Furthermore, from the comparison of hydride properties of Ti₇₅Mg₂₅ alloy with BCC phase synthesized from β-Ti and α-Ti, alloy with β-Ti easily absorbed hydrogen at the room temperature, while alloy with α-Ti hardly reacted with hydrogen. In addition, the lattice parameter of Ti–Mg with β-Ti was 0.326 nm, and the strain was lower than alloy with α-Ti. However, Ti₇₅Mg₂₅ after hydrogenation was transformed into TiH₂.

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Biaxial tensile tests of 6000 series aluminum alloy sheets with different density cube textures were carried out using cruciform specimens. The specimens were loaded under linear stress paths in a servo-controlled biaxial tensile testing machine. Plastic orthotropy remained coaxial with the principal stresses throughout every experiment. Successive contours of plastic work in stress space and the directions of plastic strain rates were precisely measured and compared with those calculated using selected yield functions: the von Mises, Hill's quadratic and Yld2000-2d [Barlat, F. et al., Int. J. Plasticity, 19 (2003), 1297–1319]. The Yld2000-2d yield functions with exponents of 12 and 6 are capable of reproducing the general trends of the work contours and the directions of plastic strain rates observed for test materials with high and low cube textures, respectively. Hydraulic bulge tests were also conducted and the variations of the thickness strain along the meridian directions of the bulged samples were compared with that calculated using finite element analysis (FEA) based on the Yld2000-2d yield functions with exponents of 12 and 6. The differences of cube texture density cause significant differences in the strain distributions of the bulged specimens, and the FEA results calculated using the Yld2000-2d yield functions show good agreement with the measurement results.

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Magnesium alloys are remarkably corroded in chloride environments. The fundamental corrosion behavior of Mg–6 mass% Al alloy cast into copper mold has been conducted through the polarization test and electrochemical impedance spectroscopy. Metallographic characteristics were evaluated by optical microscopy using the sample in the condition of as cast, as solution-treated, as under-aged for 172.8 ks and as over-aged for 864 ks. Corrosion potential was different from microstructure in Mg–6 mass% Al copper mold castings with same composition. Pitting potential was equal in Mg–6 mass% Al alloy castings with different microstructure, and the protection film dissolution potential was same. Charge transfer resistance of Mg–6 mass% Al alloy with single phase microstructure in the condition of as solution-treated and as over-aged was large, on the other hand, with double phase microstructure in the condition of as cast and as under-aged was small.

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