The mechanical and electrical properties of metallic materials are influenced by the crystallographic structure of the material. Generally, burnishing is a surface finishing method that utilizes hard tools (such as rollers) to get smooth surface. In this study, the localized or selective crystal structure improvement through burnishing processing and heat treatment to fabricate functionally graded materials are proposed. In the experiments, pure iron rods, subjected to strain relief annealing and outer diameter turning, were processed using burnishing under various conditions. After burnishing, the specimens were heat treated at 600°C to induce localized static recrystallization and improve grain size. The metal structure observation results showed that static recrystallization occurred within 5 minutes of heat treatment and refining the average grain size. Then, tensile tests were conducted to investigate the changes in material strength. The heat-treated specimen exhibited improved yield strength and tensile strength compared to the turned or burnished specimens. It was indicating that burnishing combined with heat treatment effectively refines the crystal grains, leading to enhanced material properties.
