Ti-6Al-4V合金MIM焼結体の引張特性に及ぼす相対密度および酸素量の影響

抄録

The properties of sintered Ti-6Al-4V alloy compacts have been clarified by using various mixed or Ti-6Al-4V alloy powders under the various process conditions. From these studies, there were tendencies that the tensile properties of sintered Ti-6Al-4V alloy compacts were affected by oxygen content and relative density of sintered compacts rather than process conditions. In this study, the properties of injection molded Ti-6Al-4V alloy compacts obtained from previous studies were comprehensively investigated to clarify the effect of oxygen content and relative density on the tensile properties. The tensile strength of injection molded Ti-6Al-4V alloy compacts was significantly increased with increasing the oxygen content of sintered compacts up to 0.5 mass%, and the strength also increased with increasing the relative density of sintered compacts. Although the elongation of injection molded Ti-6Al-4V alloy compacts reduced drastically at above 0.35 mass% of oxygen content, they showed excellent ductility above 10 % of elongation up to 0.35 mass% of oxygen content. Eventually, the tensile strength (σ) of injection molded Ti-6Al-4V alloy compacts were greatly correlating with oxygen content (O) and relative density (ρ) of sintered compacts as shown in the experimental equation: σ (MPa)=700O (mass%)+10ρ (%)-315