Probing the Phase Composition and Surface Roughness in the Biological Response of Additively Manufactured Titanium Alloy Bioimplants

Titanium alloys, mainly Ti-6Al-4V, are renowned for their impressive strength-to-weight ratio and stand as some of the most widely used metallic materials for bioimplants. Additive manufacturing introduces a paradigm shift in the short turnaround times for the availability of such implants. The biological performance of these implants is critical to ensure their success and is understood to be affected by a variety of factors, including surface characteristics and phase composition of the material, often determined by the manufacturing approach. The experimental investigation of the difference in biological performance caused by surface roughness and phase compositions resulting from manufacturing methods that involve laser powder bed fusion (LPBF) and hot isostatic pressing (HIP) has been conducted. Surface roughness was found to be the prevailing effect over the reported phase composition difference, with a relatively rougher surface seeming to be better for biological performance in this contribution. Meanwhile, HIP-ed Ti-6Al-4V samples exhibit better cell viability compared to that of the as-built LPBF-ed Ti-6Al-4V samples.