Hardmetal scrap and TiC-NiMo reinforced Fe₃Al claddings: A sustainable solution with enhanced wear resistance and thermal stability

Abstract

Iron aluminide (Fe₃Al)-based claddings are promising alternatives to Co-, Cr-, and Ni-based wear-resistant hardfacings, offering an excellent balance of properties with a significantly lower environmental impact. Reinforcing Fe₃Al claddings with additional hard phases enhances their wear resistance and high-temperature performance. Sustainable solutions can be achieved by incorporating recycled hardmetal scrap (HMS) or environmentally favorable phases like TiC-NiMo cermets. Therefore, we studied the impact of reinforcing Fe₃Al-based claddings with 70 vol% HMS or TiC-NiMo cermets using a laser metal deposition (LMD) process. Thereby high room temperature hardness levels of 1008 ± 52 HV10 and 1087 ± 43 HV10 are obtained, respectively, and nearly linear hardness decrease with increasing temperature, even allows for ~600 HV10 at 700 °C, indicating excellent mechanical stability. The individual phases formed within the reinforced claddings exhibit ~36 GPa for WC, ~32 GPa for precipitations W₂C, ~25 GPa for TiC, and ~7.8 GPa respectively ~7.2 GPa for the Fe₃Al matrix. The combination of a high volume fraction of hard phases and the relatively hard Fe₃Al matrix ensures strong wear resistance. Under low-stress abrasion at room temperature, the wear rates were 0.0018 mm³/m (HMS reinforced) and 0.0047 mm³/m (TiC-NiMo reinforced). At high-stress conditions, wear rates were ~0.04–0.05 mm³/m at 20 °C and ~0.055 mm³/m (HMS reinforced) and ~0.068 mm³/m (TiC-NiMo reinforced) at 700 °C. When benchmarked against conventional hardfacing materials, these reinforced Fe₃Al-based claddings demonstrate competitive performance, offering an environmentally sustainable and mechanically robust solution for wear-resistant applications.