Microhardness of pore walls in porous titanium prepared with novel powder metallurgy

Owing to the adjustable mechanical properties, porous titanium as bone substitute can reduce the effect of stress shielding. Microhardness and its distribution on pore walls are good factors to determine the microstructure of porous titanium related to the wear and corrosion resistance in vivo. In the procedure of novel powder metallurgy, porous titanium was prepared after space holders as the second phase were removed during heat treatment. Through changing the compaction pressure, sintering temperature or holding time, porous bodies with different sintering index were prepared. The effect of the friction between die wall and powders or between powders themselves can be reduced by changing the compaction pressure. The mean hardness H _m and homogeneous index HI are used to determine the homogeneity of porous structures. In order to gain specimens with high sintering index or high microhardness, sintering at higher temperature is preferred for longer holding time.