Effect of Thermal Fatigue Loading on Tensile Behavior of H13 Die Steel with Biomimetic Surface

Biomimetic surface is an effective ways to promote the performance grade and applied range of materials without altering their substrate. Many improved properties such as resisting fatigue, enduring wear, etc, have been achieved by applying biomimetic morphology or structure to some engineering material surfaces. In this paper, aiming to reveal the relationship between thermal cracking behavior and mechanical properties of engineering materials with biomimetic surface, biomimetic specimens were fabricated using laser technique by imitating the heterogeneous structure on the surface of plant leaves. The effect of thermal fatigue cycling on the tensile properties of H13 die steel specimens with different surfaces (several types of biomimetic surfaces and a smooth surface) was compared and investigated. As a result, due to the coupling effects of the morphological features on the surface and the microstructure characteristics within unit zone, these specimens with biomimetic surface exhibit remarkably enhanced Ultimate Tensile Strength (UTS) and 0.2% Yield Strength (YS) compared with reference specimens while corresponding ductility remains largely unaffected even heightened, whether the thermal fatigue loads or not. The relative mechanisms leading to these improvements have been discussed.