The Influence of Mo Additions on Physical, Microstructure and Mechanical Properties in Commercially Pure Ti Manufactured by MIM Process

Abstract

Molybdenum (Mo) is one of the beta-phase stabilisers in titanium, garnering significant interest by modifying the properties of commercially pure Ti (CP-Ti) suitable for biomedical applications. Being a non-toxic alloying element with reasonable cost, Mo can enhance mechanical properties through solution strengthening. In this study, five amounts of Mo content (0, 5, 7.5, 10, 15 wt.%) were added to CP-Ti manufactured by the metal injection moulding (MIM) process. Three sintering temperatures of 1100, 1150 and 1250 C for 4 h were applied. The properties of the sintered specimens were evaluated through density, impurity contents, microstructure, tensile testing, and observation of the fracture surfaces. The results indicate that higher Mo contents lead to an increased amount of beta phase and higher tensile strength from 600 to 1100 MPa with 0 to 15 wt.% Mo. However, excessively high Mo content contributes to low ductility due to the formation of TiC precipitated at the grain boundaries. In this study, the 5 wt.% Mo addition specimen shows the most balanced mechanical properties.