Advanced titanium materials processed from titanium hydride powder

Advanced Ti materials include Ti, Ti alloys and Ti-matrix composites with significant advantages of higher performance, lower cost, and wider applications relative to their conventional counterparts. Titanium hydride (TiH2) powder offers many advantages in producing advanced Ti materials by powder metallurgy, resulting in high relative density, novel microstructure, and competitive mechanical properties. Furthermore, using TiH2 powder can overcome the performance-cost trade-off of advanced Ti materials and thus accelerate their indus-trial application. Hence, processing of advanced Ti materials from TiH2 powder attracted serious attention in the past decades. This review summarizes the research progress on the dehydrogenation mechanism and resultant effect of TiH2 powder, the interrelation between processing technologies, microstructures, and mechanical properties of advanced Ti materials, and the influence of Kirkendall's pores (porosity induced via the Kirkendall effect) on mechanical properties of Ti matrix composites. It is hoped that this review will provide significant insight into fabricating cost-effective advanced Ti materials based on TiH2 powder.