Effect of CeO₂ Addition on Friction and Wear Properties of Selective Laser-Melted TC4 Alloys

Abstract

Titanium alloys have broad application prospects.In order to improve the forming quality and wear resistance of titanium alloys,selective laser melting (SLM) technology was used to prepare TC4 alloys,and the TC4 alloys were further modified by adding different contents(0, 0.10%, 0.15%, 0.20%, 0.25%) CeO2.Subsequently, XRD, SEM, electronic universal testing machine, friction and wear testing machine and three-dimensional optical profilometer were used to explore the effect of CeO2 content on the microstructure, phase composition,mechanical properties and friction and wear properties of TC4 alloy.Results showed that compared to the original TC4 alloy, the TC4 alloy obtained by selective laser melting technology with adding an appropriate amount of CeO2 possessed refined structure, strong mechanical propensities, low friction coefficient and wear amount and weak effects of adhesive wear and abrasive wear.When the CeO2 content was 0.15%,the hardness of the as-obtained sample reached 356.8 HV, the yield and tensile strengths reached 1 027 MPa and 1 293 MPa, far exceeding the level of forgings.Meanwhile, the average friction coefficient and wear amount reached the lowest values, which were 0.412 and 3.729×10－2 mm3, respectively, and the wear mechanisms were slight adhesive and abrasive wear.

Keywords

• selective laser melting； tc4 titanium alloy； rare earth modification； tribological properties