Revealing the Microstructure Influence in Scratch Tests of Additively Manufactured 316L Stainless Steel Under Light-Loading Conditions

Mechanical wear is a major cause for performing a second surgery among implant patients. To increase the longevity of these implants, the tribological properties of the utilized alloys must be understood on a fundamental level. Additively manufactured (AM) parts are known to exhibit unusual mechanical properties owed to a nonconventional microstructure. This work investigates single-asperity, single-scratch testing of AM 316L stainless steel under light loading conditions. The load profiles ranged from 10 mN to 500 mN in both step and ramp modes with a fixed scratching speed of 50 μm/s. The aim of the study was to observe and establish relationships between the microstructure, wear, and friction. Fluctuations in friction were attributed to uneven ridge formation along the wear track. These uneven ridges were directly correlated with the grain’s crystallographic orientation. The results herein demonstrate that microstructure can provide rich insights towards mitigating wear debris generation in AM alloys.