The Experimental Research Of Drilling CFRP Based The Complex Helical Drill

Carbon fiber composite materials (CFRP) is a carbon fiber reinforced material, CFRP is characterized by high strength and specific stiffness, fatigue resistance, good heat performance, carbon fiber composite material has been widely used in military and civil field. Because the CFRP has the characteristics of high hardness, its hardness is close to the hardness of high speed steel, so cutting tool wear easily when processing; on the other hand, due to CFRP anisotropy and low interlaminar strength, the process is easy to produce the defects such as delamination, tear. It is particularly acute in the drilling process. However, drilling technology is an important process in CFRP processing, so the drilling CFRP research has been the focus of research scholars.In view of the CFRP in the drilling process is easy to produce delamination, tear and burr defects such as problems, carrying out drilling CFRP with complex helical dill. The main works have been done as follows:(1) Overview of carbon fiber composites, including the definition of CFRP, the application and research status at home and abroad in drilling process, summarizes various problems in the process of drilling CFRP, and introduce the characteristics of the complex helical surface drilling and grinding principle, the advantages of drilling CFRP.(2)The mathematical model of complex helical dill was established according to principle of grinding, and get the mathematical model of the drill flank and the flute.Solving equation of geometry parameters was established, relationship between drill point geometry parameters and grinding parameters was analyzed, and provide theoretical basis for the grinding technology of complex helical drill.(3) Using high speed steel standard twist drill to grinding complex helical drill point, and study the effect of grinding parameters on drill point geometry parameters, the reasonable and controllable parameters were selected which provided scientific guidance for grinding tests.(4)The defects in the process of drilling CFRP and the cause of the defects are analyzed. Due to the drilling force directly affect the production of various kinds of defects, so the drilling force is analyzed.(5) Complex helical drill point and common drill points are used in the drilling experiment, changing grinding parameters in the contrastive experiment, and analyze different drill points on the drilling force and drilling quality, and find the process range and reasonable drill shapes for drilling CFRP. The drilling quality has been compared between the high speed steel and carbide drill.