The metal injection molding process was applied to produce a near-alpha titanium alloy using a mixture of Ti and pre-alloyed powders, and that of elemental powders. The effect of sintering conditions on the mechanical properties and microstructures of the sintered compacts were investigated. To estimate the alloying of each element, characteristic X-ray images were also measured by means of electron probe micro analyzer.
The sintered compacts using a mixture of Ti and pre-alloyed powders showed higher density and mechanical properties as compared to the compacts using a mixture of elemental powders. The former sintered at about 1323 K for 14.4 ks showed a sufficient alloying of each element, but the latter, even sintered at about 1473 K for 14.4 ks, showed an insufficient alloying of molybdenum which was hardest diffusion element in this titanium alloy. Eventually, the mechanical properties of the compacts using a mixture of Ti and pre-alloyed powders were comparable to those of the wrought alloys.