Investigation of the strengthening mechanism of thermal-assisted laser material processing on the cutting performance of micro-textured tools

Abstract

Surface texturing of tools is an effective method for enhancing their cutting performance. Research on micro-textured tools has evolved from a focus on applications to an emphasis on performance enhancement. Laser processing is the most widely used method for preparing micro-texture; however, processing defects that commonly occur during the preparation process, along with inherent limitations in the process, significantly hinder the broader application of the tool. Therefore, this study focuses on cemented carbide tools and investigates the combination of thermal-assisted processing and laser technology to explore the influence mechanism of thermal-assisted temperature on the surface morphology, element distribution, and mechanical properties of micro-textured cemented carbide. A milling test platform was developed to analyze the evolution of the milling performance of micro-textured tools under the thermal-assisted process. The optimization of thermal-assisted process parameters was achieved using the AHP-rank sum ratio comprehensive evaluation method. The results indicate that the thermal-assisted process effectively reduces residual stress and the temperature gradient during laser processing. It also helps to control the uneven material distribution caused by the Marangoni convection effect, preventing crack nucleation and reducing the formation of cracks. Additionally, the process improves the elastic modulus and microhardness of the surface, enhances the structural stability of the micro-texture, and strengthens the bonding with the coating. Furthermore, it improves the wear resistance and friction-reducing performance of the tool surface, while also reducing milling forces, noise, tool wear, and surface roughness of the workpiece. Using the AHP rank-sum ratio method for a comprehensive evaluation, it was found that the overall milling performance of the tool is optimal at a thermal-assisted temperature of 673.15 K. This study offers new insights for addressing the preparation process defects of high-performance tools and enhancing their cutting performance. Most of the research on thermal-assisted laser material processing technology only stays in the surface observation stage. This study not only focuses on repairing the defects caused by the micro-texture preparation process, but also focuses on how this repair can improve the actual working performance. Combining theory with practice to solve practical problems in the cutting process.