Microstructure and Properties of Ti-8Mo-12Fe and Ti-8Mo-8Cu alloys with Cr_3C_2 Additives Produced in the Powder Metallurgy Processes

摘要

Titanium base composites with a 3% wt of Cr_3C_2 additives were processed by powder metallurgy using vacuum sintering between 1423～1523 K. Different elements of the alpha-beta type Ti alloys were compared. Fe-based alloys accelerate the sintering process. Mo proves to be a good candidate for solution strengthening and Cu effectively increase the material ductility of the Ti matrix. Therefore Cr_3C_2 and Mo are both very suitable β stabilized additives for reinforcing Ti-based composites. The development of the plastic deformation of the ternary alloys has been observed and the morphology of the eutectic alloy Ti-8Mo-8Cu causing refinement and supersaturating of the β phase is crucial factor for improving the ductility of the Ti alloys. On the contrary Ti-8Mo-12Fe induced a change of the morphology of the eutectic and increase fraction. The aim of this project is to compare the sintering behavior and evolving phases using SEM images taken from polished specimens and bending testing fractured surfaces.