Optimum Wear Resistance Achieved by Balancing Bulk Hardness and Work-Hardening: A Case Study in Austenitic Stainless Steels

Wear, which exists in all industries and walks of life, causes tremendous economic losses and even major disasters. To prevent damage caused by wear, Archard’s theory suggests the use of materials with higher hardness. However, such materials are minimally formable and difficult to manufacture. Recent studies have reported that strain hardening is another factor that significantly affects wear resistance. In this study, to investigate the relative potential of each of these factors and examine the balance between the hardness and work-hardening properties under various working conditions, we selected 321 austenitic stainless steel as a candidate material. Cold-rolling, which improves the base strength of the material, was used to develop strain-induced α′-martensite. Simultaneously, the strain-hardening capability of the material was decreased. The wear resistance and corresponding failure mechanisms were evaluated using the ball-on-disc test under various loading conditions. The results indicate that wear resistance depends on the bulk hardness and loading conditions used. A series of microstructural analyses revealed that the wear resistance is closely related to the base strength and hardening capability of the material. Therefore, this study establishes an optimum hardness–strain hardening balance and elucidates the design of low-hardness, high-wear-resistance materials for future applications.