Tribology, the study of friction, wear, and lubrication, plays a critical role in the performance of manufactured components, particularly in the emerging field of additive manufacturing (AM). While AM allows for the fabrication of complex geometries, the as-built components often suffer from surface roughness and suboptimal mechanical properties, necessitating post-processing treatments to enhance their usability. In this paper, a specific heat treatment sequence, including main quenching, intermediate quenching, and tempering, was applied to stainless steel 316L samples to improve their mechanical characteristics. The main quenching involved heating the samples to 1000°C for 30minutes, followed by water quenching. The intermediate quenching followed a similar process at 750°C. The heat-treated samples (HT-1 and HT-2) underwent different tempering stages. The HT-1 samples were selected for tribological testing due to their lower residual stresses and higher hardness compared to HT-2 samples, with both samples demonstrating similar ductility. HT-1 samples were tested against six different hard counter body materials under varying surface roughness conditions achieved through electrochemical polishing. The electrochemically fully finished (ECP) samples achieving the lowest coefficient of friction (COF) compared to as-built samples. Wear mechanisms varied with the counter body materials: adhesive wear and tribo-oxidation were dominant against hardened steel, alumina (Al2O3), boron carbide (B4C), and silicon carbide (SiC), while abrasive wear was predominant against tungsten carbide (WC) and titanium carbide (TiC).
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