The effect of post-sintering treatments on the fatigue and biological behavior of Ti-6Al-4V ELI parts made by selective laser melting

• Published in: Journal of the mechanical behavior of biomedical materials Vol. 71; pp. 295 - 306
• Main Authors: Benedetti, M., Torresani, E., Leoni, M., Fontanari, V., Bandini, M., Pederzolli, C., Potrich, C.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Ltd 01-07-2017
• Subjects: Biocompability; Fatigue; Hardness; Hot isostatic pressing; Humans; Lasers; Materials Testing; Prostheses and Implants; Selective laser melting; Shot peening; Surface Properties; Ti-6Al-4V ELI; Titanium - analysis; Fatigue; Shot peening; Ti-6Al-4V ELI; Selective laser melting; Hot isostatic pressing; Biocompability
• ISSN: 1751-6161; 1878-0180
• DOI: 10.1016/j.jmbbm.2017.03.024

Fatigue resistance and biocompatibility are key parameters for the successful implantation of hard-tissue prostheses, which nowadays are more and more frequently manufactured by selective laser melting (SLM). For this purpose, the present paper is aimed at investigating the effect of post-sintering treatments on the fatigue behavior and biological properties of Ti samples produced by SLM. After the building process, all samples are heat treated to achieve a complete stress relief. The remaining ones are tribofinished with the aim of reducing the surface roughness of the as-sintered condition. Part of the tribofinished samples are then subjected to one of the following post-sintering treatments: (i) shot peening, (ii) hot isostatic pressing (HIP), and (iii) electropolishing. It is found that shot peening and HIP are the most effective treatments to improve the high and the very-high cycle fatigue resistance, respectively. At the same time, they preserve the good biocompatibility ensured by the biomedical Titanium Grade 23.