Tribological Behavior of 316L Stainless Steel Fabricated Using Metal Extrusion Additive Manufacturing Under Dry and Simulated Body Fluid-Lubricated Conditions

Herein, the tribological behavior of 316L stainless steel (SS) fabricated using metal extrusion additive manufacturing (MEAM) is investigated both under dry and simulated body fluid (SBF)-lubricated conditions. The results and mechanisms are compared with those of 316L SS fabricated via selective laser melting (SLM) and hot rolling (HR). Under dry-friction conditions, the 316L SS fabricated via MEAM shows inferior tribological performance compared with those fabricated via SLM and HR, primarily because of its lower initial hardness and better plasticity, which increase both abrasive and adhesive wear. Under SBF-lubricated conditions, the tribological performance of the 316L SS fabricated via MEAM is comparable to that fabricated via HR and superior to that fabricated via SLM. The wear rate of the MEAM-fabricated 316L SS is 16.8% and 3.2% lower than SLM- and HR-fabricated, respectively. The numerous pores on 316L SS serve as traps for wear particles, which contribute to the reduction of three-body wear. In terms of wear under SBF-lubricated conditions, MEAM technology appears to be a promising method for the fabrication of customized 316L orthopedic implants.