Tribological Performance of High-Chromium Cast Irons: Effect of Chromium Content, Amount of Chromium Carbides (M₇C₃) and Loading Conditions on Wear Resistance

Selecting cost-effective materials for high-wear applications requires the exploration of alternative materials such as high-chromium cast irons regarding the resulting wear resistance and energy efficiency, justifying potential cost reductions. Our study investigates the tribological performance of high-chromium cast irons depending on the adjusted chromium content (11, 15, and 30 wt.-%) and heat treatment. In this regard, the resulting microstructure, mechanical properties, and wear resistance were analyzed, comparing the performance of high-chromium cast irons with benchmarking high-carbon steel. Complementary materials characterization combined with nanoindentation revealed that an increasing chromium content induced a higher volume fraction of eutectic carbides (M₇C₃), thus improving the wear resistance. The sample containing 30 wt.-% of Cr exhibited the lowest wear rate due to its dense carbide network, which acted as a physical barrier against abrasion. While hardness remained stable, the elastic modulus increased with carbide content, indicating a greater material stiffness. Our findings underscore the importance of optimizing the alloy composition and heat treatment to improve the durability and efficiency of materials used in abrasive environments thus providing valuable insights to develop advanced tribological solutions, contributing to energy savings and reduced CO₂ emissions.

Graphical Abstract