Enhanced Wear and Corrosion Performances of Titanium Parts Fabricated by SLM Using Near-Spherical Powder for Biomedical Applications

Herein, commercially pure titanium parts (CP-Ti) are fabricated successfully by laser powder bed fusion using cost-effective ball milling (BM) near-spherical powder. The hardness, microstructure, wear, and corrosion performances of BM-Ti parts are investigated systemically. The microstructure of the fabricated BM-Ti sample consists of alpha ' phase. Compared with the sample fabricated using gas-atomized (GA) spherical powder, the BM-Ti sample exhibits higher hardness (354 HV vs 240 HV) due to grain refinement. Owing to the formation of a denser oxide film and finger gain, BM-Ti exhibits a higher corrosion resistance than that of GA-Ti and forged Ti-6Al-4 V alloy. Under the same load, taking 2 N for example, the BM-Ti sample exhibits a lower wear rate (1.03 x 10(-12) m(3) N-1 m(-1)) than that of the GA-Ti sample (1.75 x 10(-12) m(3) N-1 m(-1)), and comparable to the forged Ti-6Al-4 V alloy (0.84 x 10(-12) m(3) N-1 m(-1)). The wear mechanism of the BM-Ti sample and forged Ti-6Al-4 V alloy is abrasive wear accompanied by adhesion, while the mechanism for the GA-Ti sample is a combination of delamination and adhesion wear. Together, enhanced wear and corrosion performances of CP-Ti fabricated using low-cost BM near-spherical powder widen its applications in the fields of biomedical further.