Abstract:Raw material powder has a significant effect on the sintering of spark plasma sintering (SPS). Two kinds of WTi mixtures were used as the raw materials, one was the mixed powders of W (unmilled or milled) and Ti (or TiH2), and the other mixture was the mechanically alloyed W-Ti powders. The W-10Ti alloys were then prepared by SPS at 1400℃ for 10min. XRD, SEM and nano indentation were used to investigate the effect of raw material powders on the microstructures and properties of W-10Ti alloys. The results show that WTi alloy prepared by using milled W powders has no pure Ti phase, the content of Ti-rich phase is decreased by 44% and the nanohardness is improved by 55.7%, when WTi mixed powders are used as the raw materials. Meanwhile, TiH2 powders with fine particles is help to obtain the WTi alloy with less Ti-rich phase which is also fine and uniformly distributed in the microstructure. The obtained alloy has a relative density of 100% and its electrical conductivity, nanohardness and eastic modulus are improved by 7%, 46% and 34%, respectively, compared with those of the alloy prepared by using Ti powders. For the WTi alloy preared using the mechanically alloyed WTi powders, the content of tiny stripped Ti-rich phase is higher and the alloy has better ductility but a lower density of 96.8% and nanohardness of 2.8GPa compared with those of the alloy prepared with WTi mixed powders. Proper raw powders are a key factor to obtain excellent WTi alloy by SPS.