INNOVATIVE MATERIALS DESIGN FOR HIGH PERFORMANCE PURE TITANIUM

摘要

Through SPD-PM process, we have proposed a novel microstructural design, "Harmonic Structure", having a bimodal grain size distribution together with a specific topological distribution of fine- and coarse grained regions, i.e. fine grained network and coarse grained islands in the microstructure. Harmonic structure designed materials have exhibited outstanding mechanical properties, such as both high strength and high ductility compared with the conventional materials. In the present work, we have proposed to implement the high pressure gas jet milling process (JM) to prepare powder particles with bimodal grain size distribution by inducing severe plastic deformation layer on the surface of fine-size pure Titanium powder particles. The JMed powders were sintered by Spark Plasma Sintering (SPS) process. The mechanism of microstructural evolution and deformation behavior of the resulting compacts are presented and discussed.