Comparison Between Experimental Results and FEM Based Analyses of Flow Formed AISI 4140 Steel by Wear Rate Examination with Micro-Scratch Testing

Wear resistance plays a critical role in the longevity and performance of engineering components. Flow forming is a cold deformation method that improves material properties through strain hardening and offers insight into how deformation induced strengthening affects wear resistance. This study aims to investigate the influence of flow forming on the wear resistance of AISI 4140 steel. Although mechanical properties such as yield strength, tensile strength, and hardness have been widely studied, wear performance in strain hardened materials remains less understood. The methodology combines tensile and hardness tests, surface profilometry, and micro-scratch testing, supported by FEM simulations based on Archard's wear law and interpretation of wear mechanisms using Zum Gahr's approach to clarify wear performance in relation to material flow and microstructural changes. To bolster the experimental results, a finite element model based on Archard's equation was created using micro-scratch test data, enabling simulation of wear without further experimentation. Experimental and simulation results showed a maximum deviation of ∼5%, confirming the model's ability to capture groove depth trends governed by deformation-driven wear behavior as described by Archard's wear law. The FEM simulations, developed using isotropic hardening calibrated from tensile data, were also used to analyze wear morphology in line with Zum Gahr's approach. While the 6.3% reduction in plastic deformation type wear was obtained from experimental findings based on Zum Gahr's approach, the simulation results supported the wear depth evolution and contributed to clarifying the wear mechanism and material wear performance at elevated reduction levels in flow forming.