Combined Lubrication of Surface Texturing and Copper Covering for Broaching Tool

Abstract The broaching tool is an efficient and precisely heavy-loaded metal-cutting tool, widely used in the mass production of key components related to the aerospace and automobile industries. However, the heavy load, intense squeezing, and friction in the tool-chip contact area prevent the cutting fluid from entering the desired location. Consequently, insufficient lubrication gives rise to a high-temperature built-up edge, thereby lowering machining accuracy and efficiency. To reduce frictional force, three textures (i.e., micro-pit, stripe, mesh) are prepared on the rake face of broaching tool with laser processing technique. Afterward, textured grooves are covered with copper using the reciprocating rotational friction; this artifact enhances the system’s wettability and heat dissipation ability. Experiments approve that compared to the non-textured cutting teeth, the cutting force with the stripe-textured teeth is reduced by 7.6%. Nevertheless, the cutting force is decreased by 14.6% after covering the tool surface with copper. Obtained results indicate that the wettability of cutting fluid on the surface is improved. In addition, convex peaks on the tool surface are passivated during the reciprocating rotation of the copper bar.