Microstructure and Mechanical Properties of Sintered Ti-Cu Alloys

Abstract

The use of titanium for medical and dental applications is on the rise because of their excellent biocompatibility. However, some properties of pure titanium are not sufficient. Alloying with copper can improve mechanical properties needed for dental use. A recent research on Ti-Cu cast alloy indicated that ductility decreased with increasing copper concentration, but addition of copper improved grindability and wear resistance, with lower corrosion resistance. The objective of this research is to study sintering of Ti-Cu alloys; their microstructure and hardness, and the effect of copper content to their sintered density. Ti-Cu alloys were produced via powder metallurgy. Titanium powder was mixed with copper powder with chemical composition of 2, 4, 7 and 10 wt%. Lubricant was added in alloy powder with 0.5% of total weight, followed by cold compaction under 254 MPa pressure. Debinding and sintering was carried out at 400oC for 0.5 hr and 1000oC for 1 hr respectively in argon atmosphere. Condition with highest density was found in 10wt%Cu composition; having highest hardness of 317 Hv. Differential thermal analysis of Ti-15Cu under N2 atmosphere showed exothermic reaction at 1078oC. Phase formation of the sintered alloys followed the Ti-Cu equilibrium phase diagram.