Investigation of the effects of laser surface modification on wear performance in AISI D2 tool steel

This study investigates the tribological behavior of different laser texture patterns on AISI D2 cold work tool steel using a ball-on-disk wear test rig under both dry sliding and MoS2 solid lubricant conditions, at various loads (2N and 4N) and sliding durations (15 and 30 minutes). Experimental results demonstrated that laser surface modification significantly improved wear resistance and friction properties across all textured surfaces. Under dry sliding conditions at 4N load and 30 minutes sliding duration, the highest volume loss (0.894x10-3 mm3) and friction coefficient (μ=0.90) values were obtained on the untextured surface. In contrast, the large circle pattern exhibited superior performance under all conditions, reducing volume loss by 19% (from 0.801x10-3 mm3 to 0.647x10-3 mm3) and friction coefficient by 24% (from μ=0.90 to μ=0.68) compared to the untextured surface under 2N load and 15 minutes sliding duration. The application of MoS2 solid lubricant further enhanced performance, with the most effective results achieved on the large circle patterned surface. The combination of large circle pattern and MoS2 lubricant exhibited excellent performance with the lowest volume loss (0.106x10-3 mm3) and minimum friction coefficient (μ=0.109) values among all test conditions under 2N load and 15 minutes sliding duration. Compared to dry conditions, improvements of 84% in volume loss and 82-84% in friction coefficient were achieved. SEM, EDS, and 3D profilometer analyses revealed that the dimples in textured surfaces effectively trapped wear debris and wear depth decreased by 85-90% (from 4 μm to 0.4-0.6 μm) in the presence of MoS2. Although increased load and sliding duration raised volume loss across all surfaces, laser-textured surfaces demonstrated superior resistance even under high load conditions. In conclusion, the combined use of optimum laser texture patterns and MoS₂ lubricant significantly improves the tribological performance of AISI D2 tool steel, offering promising solutions for extending tool life in industrial applications.