High-temperature wear performance of hardmetal scrap reinforced iron aluminide claddings

Abstract

With 3 % of the world's energy consumption devoted to re-manufacturing worn parts, sustainable alternatives utilizing recycled materials are increasingly crucial. Iron aluminides, known for their mechanical stability up to 600 °C, present themselves as promising substitutes for Co- and Ni-based claddings in high-temperature applications. In this study, we enhance the performance of laser metal deposited Fe₃Al-based claddings by incorporating recycled hardmetal scrap, with average particle sizes of 300 and 500 μm and Co contents of 4–8 wt%. Our investigations reveal a significant increase in hardness, from approximately 270 HV10 (Fe₃Al-base) to 757 ± 12 HV10 with the addition of 50 vol% hardmetal scrap. This improvement is due to the presence of WC/W₂C phases, which exhibit hardness levels of 31.3–38.1 GPa or 19.2–24.9 GPa respectively, concomitant with the increased hardness of the Fe₃Al-based matrix, achieving 6.8–7.6 GPa. Notably, this cladding maintains a hot hardness of 509 ± 62 HV10 at 600 °C and demonstrates an abrasive wear resistance of 0.0391 ± 0.0004 mm³/mm at 20 °C and 0.0466 ± 0.0003 mm³/m at 700 °C during high-stress and 0.007 ± 0.001 mm³/m at 20 °C during low-stress abrasion tests. Thereby, outperforming FeCrC-based as well as reinforced Ni- and Co-based hardfacings across the temperatures and abrasion modes tested (room temperature, 500 °C, and 700 °C). Our findings demonstrate that incorporating hardmetal scrap into Fe₃Al-based claddings enables the development of high-performance hardfacings with reduced environmental impact.