Binder jetting additive manufacturing of AISI M2 tool steel: Investigating the influence of sintering parameters on wear behavior

Binder Jetting Additive Manufacturing (BJAM) offers significant potential for fabricating high-performance tooling materials, yet the behavior of AISI M2 tool steel processed via BJAM remains largely unexplored. This study bridges that gap by systematically investigating the effects of sintering temperatures (1270, 1280, and 1300 °C) and cooling methods (furnace, air, and water quenching) on the tribological performance of BJAM-processed M2 tool steel. Through advanced characterization techniques, including SEM/EDS mapping, Atomic Force Microscopy (AFM), and optical topography, the study examines microstructural evolution, tribological behavior, and carbide distribution (MC, M₆C, M₂C) and their role in wear resistance. Four dominant wear mechanisms, abrasive, adhesive, oxidative, and fatigue, are identified, each influencing the material's failure modes. MC carbides are primarily responsible for abrasive wear, M₆C promotes adhesion, oxidative wear results from elevated temperatures, and fatigue wear arises from microcracks at carbide-matrix interfaces. Key findings indicate that post-processing conditions significantly impact wear performance. Water-cooled samples sintered at 1270 °C for 60 min exhibit the lowest coefficient of friction and wear volume loss, which is attributed to finer microstructure, uniform carbide dispersion, and increased hardness, which reduces abrasive wear. Conversely, higher sintering temperatures lead to carbide coarsening, grain growth, and increased wear. This study establishes a direct correlation between BJAM processing parameters and tribological properties, demonstrating its viability for tooling applications. The findings provide a foundation for optimizing BJAM-processed M2 tool steel for improved wear resistance and industrial applicability.