Evaluation of the mechanical and wear properties of titanium produced by three different additive manufacturing methods for biomedical application

Commercially pure titanium, as a widely used metallic biomaterial, was fabricated using dissimilar additivemanufacturing (AM) methods, namely selective laser melting (SLM), laser engineered net shaping (LENS) andwire arc additive manufacturing (WAAM). Microstructures as well as mechanical and wear properties of theproduced titanium samples were studied. Diverse microstructural features were related to the different linearenergy densities and cooling rates induced by each AM method. Tensile testing evaluation indicated the highestyield and ultimate tensile strengths as well as elastic energy for titanium produced by SLM. However, themaximum ductility was obtained in the WAAM-fabricated titanium due to its larger grain size and slightly higherdensification. All the mechanical properties obtained were either superior or comparable to those of cast andpowder metallurgy produced titanium. Fracture surface analysis showed the presence of mainly coarse andfinedimples for WAAM and SLM-produced samples, respectively. This was consistent with the grain size of eachsample. Wear performances and mechanisms were also examined and the results were in agreement with thevalues obtained from the hardness to elastic modulus ratios (H/EandH3/E2).