Effects of TiCl4 purity on the sinterability of Armstrong-processed Ti powder

A series of high purity and low purity powders were synthesized from TiCl4 by the Armstrong process. While both powders displayed swelling when consolidated and sintered, the lower purity powder exhibited this phenomenon in significantly lower degree. The improvement is attributed to the increase in the onset of sintering temperature, which mitigates the entrapment of volatile impurities that would otherwise lead to pore formation and growth. The net effect is that the use of a lower purity TiCl4 may beneficial in two ways: (1) it is a potentially lower cost precursor to Ti powder production and (2) the trace impurities allow higher density components to be fabricated via a typical low-cost press and sinter approach.