Comparative Investigation of Mechanical, Tribological, and Thermal Behaviour of Ti6Al4V and SS316L Alloys Fabricated Using Laser Powder Bed Fusion

Abstract

This study investigates the mechanical, tribological, and thermal properties of Ti6Al4V and SS316L alloys fabricated using the laser powder bed fusion (LPBF) technique. A comparative analysis is conducted, focusing on tensile strength, elongation, and yield strength, alongside microhardness, wear resistance, and the coefficient of friction under varying loading conditions. Ti6Al4V demonstrates superior mechanical performance with an ultimate tensile strength of 965.45 MPa and hardness of 291 HV, compared to SS316L with 506.96 MPa and 232 HV, respectively. However, SS316L exhibits higher elongation at break of 44.77% compared to 15.06% of Ti6Al4V, indicating better ductility. Tribological results reveal significantly lower wear (26.66 µm at 10 N) and coefficient of friction (0.3082 at 10 N) for Ti6Al4V, confirming its superior wear resistance under dry sliding conditions. Maximum wear obtained is 197.16 µm at 15 N in the SS316L sample. Surface topography analysis through optical microscopy images and characterized SEM micrographs reveals microstructural features critical for understanding material behaviour. XRD patterns confirm the phase compositions of both alloys, with distinct peaks showcasing the crystalline nature of the fabricated alloys. Thermal behaviour assessed through TGA-DTA indicates the stability of both alloys up to 1000°C. These findings provide valuable insights into the applicability of LPBF-fabricated Ti6Al4V and SS316L alloys for advanced engineering and orthopaedic applications.