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The ultimate tensile strength of 250 MPa, 0.2% proof stress of 150 MPa, and fracture strain of 10% at the as-cast condition for Al-1.5Mn-X alloys, were objective in this development. As ternary elements, Ca, Mg, Ti and Zn were initially chosen and the values in ¦Mk of the s-orbital energy level in alloys were adjusted to be less than 0.017. Their proof stress and fracture strain increased and decreased as ¦Mk increased, respectively. The composition of promising alloy was decided to Al-1.5Mn-2.4Mg with ¦Mk of 0.029 on the basis of the relation between tensile properties and ¦Mk. This as-cast alloy showed the · uts · 0.2 and ¾ f of 270, 135 MPa and 18% showing excellent corrosion resistance in the NaCl solution, which resulted in the approximate satisfaction of the objective. The interaction between the proof stress and dislocation density or hindrance for dislocation migration at the constant strain could be explained by ¦Mk, which might lead to the indication of solid solution hardening level using this parameter for Al-1.5Mn-X ternary alloys.

Our findings suggest that β-TCP may be an effective extender when using the induced membrane technique.

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The + type Ti-5.5Al-2Fe and type Ti-2.5Fe-2Mn-2Zr alloys have been theoretically designed, for the modification of Ti-6Al-4V and the achievement of the high tensile strength more than 1000 MPa at the solution treatment state, respectively, using ubiquitous alloying elements in order to establish the strategic method for suppressing utilization of rare metals. The utilization of the cold crucible levitation melting (CCLM) is very useful for the production of ingots, because titanium is very chemically reactive at high temperature. The experimental alloys with high purity and without contaminations from a crucible were prepared, and the homogeneous melt was also achieved by the diffusion mixing effect of CCLM. The microstructure, phase stability, strength, corrosion-resistance and workable properties of the design Ti-5.5Al-2Fe alloy, were comparable to those of Ti-6Al-4V. In contrast, the solution heat treated Ti-2.5Fe-2Mn-2Zr alloy showed the tensile strength of 1200 MPa, and the 1.3 times increase in the specific strength compared with Ti-15Mo-5Zr-3Al. The alloy design can be successfully carried out even using ubiquitous alloying elements by the d-electrons concept, which leads to the establishment of one method for the strategic utilization of rare metals.

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The temperature dependence of specific resistivity and thermal conductivity for some Sn-Zn alloys was measured to use their values in electrical and thermal calculations on the basis of Ohm's and Fourier's laws, in order to obtain the temperature-distribution in lead-free fuse elements of electric power line. The interaction between microstructures and their properties was also investigated in Sn-Zn alloys. Specific resistivity and thermal conductivity could be estimated as a function of temperature and alloy composition in the compositional ranges classified from the standpoint of continuity or non-continuity of constituent phases such as primary Zn, Sn-solid solution and eutectic in microstructures of Sn-1 to 100Zn alloys. In the proposed estimations, not only volume fraction of Zn and Sn-solid solution phases but morphologies of both phases were considered in Sn-Zn alloys.