Study on Burr Formation and Tool Wear in Drilling CFRP and Its Hybrid Composites

As contemporary emerging materials, fiber-reinforced plastics/polymers (FRP) are widely used in aerospace automotive industries and in other fields due to their high strength-to-weight ratio, high stiffness-to-weight ratio, high corrosion resistance, low thermal expansion and other properties. Drilling is the most frequently used process in industrial operation for polymer composite laminates, owing to the need for joining structures. However, it is a great challenge for operators to drill holes in FRP materials, due to the non-homogenous and anisotropic properties of fibers. Various damages, such as delamination, hole shrinkage, and burr and tool wear, occur due to the heterogeneous and anisotropic nature of composite laminates. Therefore, in this study, carbon fiber reinforced polymer (CFRP)/aramid fiber reinforced polymer (AFRP) hybrid composites (C-AFRP) were successfully synthesized, and their drilling characteristics, including burr generation and tool wear, were also mainly investigated. The drilling characteristics of CFRP and C-AFRP were compared and analyzed for the first time under the same operating conditions (cutting tool, spindle speed, feed rate). The experimental results demonstrated that C-AFRP had higher tensile strength and good drilling characteristics (low thrust and less tool wear) compared with CFRP. As a lightweight and high-strength structural material, C-AFRP hybrid composites have great potential applications in the automobile and aerospace industries after the slight processing of burrs generated during drilling.

Automated summary

Fiber-reinforced plastics/polymers (FRP) are widely used in various industries for their high strength-to-weight ratio and other properties. Drilling holes in FRP materials can be challenging due to their non-homogenous and anisotropic properties, resulting in various damages. In this study, carbon fiber reinforced polymer (CFRP)/aramid fiber reinforced polymer (AFRP) hybrid composites (C-AFRP) were synthesized and their drilling characteristics were investigated, showing that C-AFRP had higher tensile strength and better drilling characteristics compared to CFRP.