Sliding wear behavior of a Laves phase-strengthened CrFeNiNb0.158 alloy at room and elevated temperatures

Abstract

Face-centered-cubic (FCC) compositionally complex alloys (CCAs) are recognized for their exceptional mechanical properties, rendering them promising candidates for demanding engineering applications. However, a significant challenge faced by these alloys is their limited wear resistance. In this study, we addressed this issue by introducing 5 at.% Nb into an equiatomic FCC CrFeNi alloy, thereby creating a Laves phase-strengthened CrFeNiNb0.158 alloy, and investigated its sliding wear behavior at both room and elevated temperatures. Our findings reveal a substantial improvement in the wear performance of the Laves phase-strengthened CrFeNiNb0.158 alloy. Specifically, at room temperature (RT), the alloy exhibited a remarkable 62 % reduction in wear rate compared to the CrFeNi alloy. Furthermore, at an elevated temperature of 600 °C, the wear rate decreased by approximately 95 %, primarily attributed to the formation of a lubricating (Cr, Fe)2O3 oxide layer. Through detailed analysis, we identified the wear modes as abrasive wear at RT and oxidative wear at elevated temperatures. These results provide valuable insights for designing wear-resistant FCC CCAs by utilizing Laves phase strengthening and incorporating elements prone to oxidation to facilitate the formation of a protective oxide layer at elevated temperatures.