Experimental investigation on mechanical drilling of a newly developed CFRP/Al co-cured material

Abstract

The use of material combination composed of carbon fiber reinforced polymer (CFRP) and metals is getting increased attention in many industries. The newly developed CFRP/metal co-cured material is one of the most popular compound structures and is mainly applied to the attitude control flywheel (ACL) in the military light agile satellite. Drilling is still a challenge for manufacturers in the assembly chain of ACL because of the anisotropy of CFRP and difficult-to-cut metals. In this work, the drilling machinability of a newly developed co-cured material consisting of M30/AG80 CFRP and 7050Al is evaluated by a standard twist drill. The significance of this paper aims to reveal the key cutting phenomena including thrust forces, drilling temperatures, and hole quality during drilling the assigned co-cured material. The mechanism controlling the parametric effects on the interfacial cutting response was also revealed. The results highlight the impact of tool–work contact ratio on the evolution of thrust forces and drilling temperatures. Besides, grooves and matrix degradation are two typical defects on the hole surface of CFRP layers while chip adhesion is the case for Al layer. The mechanical action plays a predominant role in determining the cutting response of the upper interface whereas the thermal effect does greatly affect the condition of the lower interface.