The compositions of β type Ti alloys having shape-memory ability above 373K and tensile strength of 600MPa, were optimized by both parameters proposed in the d-electrons concept. Promising alloys were Ti-6Mo, Ti-6Mo-3Al, Ti-6Mo-3Cu and Ti-6Mo-2Al-1Cu in mole%. Their ingots with high purity and without contamination from the crucible used, were produced by cold crucible levitation melting. They consisted of both β and α” phases after the cold roll and heat treatment. They showed shape memory ability above 510K, and shape recovery rate of 25-55%. Ti-6Mo-3Al, which had the highest shape recovery rate and no appearance of ω phase, showed constant recovery values in load-unload-heat tests to nine cycles. Design alloys showed tensile strengths ranging from 610 to 710 MPa. These results suggest that the phase stability, shape memory ability and tensile strength can be predicted by alloying parameters.

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  In this study, the effects of various surface treatments on the glossiness of AC4CH-T6 casting and newly developed bright aluminum alloy casting were examined.
  With the AC4CH-T6 casting, it was difficult to obtain a bright surface by buffing because of the surface irregularity between the hard eutectic silicon and aluminum matrix. On the other hand, with the developed silicon-free alloy casting, it was possible to produce a bright surface by buffing, and this glossiness was superior to that of the AC4CH-T6 casting covered with decorative chrome electroplating. The glossiness of the developed casting decreased sharply after chemical polishing, depending on the generation of local dissolution close to the intermetallic compound and pin-hole. However, electropolishing under optimum conditions helped realize a smooth and bright surface.
  As with anodization from sulphuric acid solution, glossiness of the developed alloy casting decreased because of the prior dissolution of the intermetallic compound. However, anodization from the developed solution suppressed this dissolution, forming a uniform oxide film. As a result, bright surfaces could be produced for the developed alloy casting by anodization.

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