By using a processing map and result of FEM simulation, an artificial hip joint stem made of Co-29Cr-6Mo-0.12N alloy was fabricated using a non-isothermal hot semi-closed die forging method. The optimum hot forging conditions (i.e., initial work temperature and pressing speed) were determined using a processing map and FEM simulation. It was observed that the microstructure of the forged stem, which markedly varied from position to position, contained both the fine dynamic recrystallized grains and a deformed microstructure. The variation in the microstructure is thought to be due to a decrease in the temperature of the stem during the hot forging. It is found that the combined used of a processing map and FEM simulation is a very useful for manufacturing artificial hip joint stems made of Ni-free Co-29Cr-6Mo-0.12N alloy.
