Drilling CFRP Laminates by Dual-Axis Grinding Wheel System With Copper/Diamond Functionally Graded Grinding Wheel

Abstract

This study aims to investigate the drilling performance of a copper/diamond functionally graded grinding wheel (FGGW) fabricated by centrifugal sintered-casting for carbon fiber-reinforced plastic (CFRP) laminates by originally designed dual-axis grinding wheel (DAGW) system. The copper/diamond FGGW was also originally designed and fabricated by the centrifugal sintered-casting to suppress abrasive-grain wear and reduce the consumption of abrasive grains in our previous study. Drilling tests were carried out over 50 holes in dry machining. Thrust force was evaluated with force sensor during drilling test. Hole diameter, roundness, and roughness were measured to assess hole quality. Drill chips were observed by scanning electron microscope (SEM) to investigate chip morphology. Precision drilling without burring and delamination was achieved in CFRP laminates. Good hole-quality was still obtained over 50 holes due to the low thrust force during drilling. Specific three-dimensional (3D) drilling process of the DAGW system enabled stable and precision drilling with low thrust force in CFRP laminates continuously.