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To narrow down the candidates of the alloying element powders for Ti-5Al-1Fe products manufactured with BE/PM, two master alloy powders, atomized spherical 5Al-1Fe and crushed-andground polyhedron 5Al-1Fe-4Ti ternary powders, were investigated with emphasizing on homogeneity of alloying elements, Al and Fe, in sintered Ti-5Al-1Fe. Intense Al segregation is recognized in the sintered specimen manufactured using 5Al-1Fe atomized powders, while strong segregation is not observed in the specimen manufactured using 5Al-1Fe-4Ti crushed-and-ground powders. Density of sintered specimen manufactured using 5Al-1Fe atomized powders is lower than that manufactured using 5Al-1Fe-4Ti crushed-and-ground powders. Al segregation and lower sintered density are probably caused by lower density of the powder substance, high flowability of spherical powders and phase constitutions some of which have low melting points. Those factors have to be taken into account to manufacture sintered titanium alloys with high homogeneity by BE/PM.

To challenge the significant reduction of manufacturing cost of Ti thin sheet or foil in the future, manufacturing of Ti foil by electrodeposition route was studied with emphasizing on factors affecting quality of the foil and separability from Mo cathode. Current density was one of the strong factors affecting soundness of deposited Ti foil and its separability from the cathode. Electrolyte bath temperature also affected soundness and separability of deposited Ti foil. Separability was closely related to interdiffusion distance of Ti and Mo, that is, shorter diffusion distance, which was brought by low temperature and low current density, led to good separability as well as good surface quality. By reflecting above knowledge, post card size Ti foil of around 0.1 mm in thickness was successfully obtained. It had good quality and could be separated from the cathode by hand. O and Fe contents were drastically decreased by this process.

To respond to the requirements for porous Ti sheet with the balanced properties of high porosity and good mechanical properties, and to optimize the manufacturing conditions of the simple powder-filling plus sintering process, effects of sintering temperatures on density and bending strength in porous Ti sheet were investigated. The optimum sintering condition was 900-950 °C for 1h to obtain porous Ti sheet with the balanced density ratio (around 40%) and high bending strength. The polyhedron shape of HDH powders contributed to those balanced properties, in which localized sintering raised bending strength with keeping high porosity (low density). Using the optimum manufacturing conditions, large sized porous Ti sheet of 400 × 800 × 0.5 mm was successfully manufactured.