Effect of chips on drilling process when drilling C/SiC ceramic matrix composite holes with brazed diamond abrasive drill

Abstract

Brazed diamond abrasive drill was suitable for drilling holes in carbon fiber reinforced silicon carbide ceramic matrix composites, but a large amount of chips could adversely affect the drilling process of the holes. Therefore, according to the chip discharge process, the chip morphology was analyzed, and the effects of chips on the axial drilling force, the hole processing quality and the drill wear during drilling were studied. The results show that the chips have an effects on the axial drilling forces, especially when drilling deep holes. The chips have little effects on the machining quality of the hole inlet, only a slight edge collapses at the hole inlet. The chips have a significant impacts on the processing quality of the hole outlet, which can cause serious fiber breakage, tear defects, and large areas of the matrix shedding. At the same time, the chip intensifies the drill wear, which not only causes slight wear such as edge collapse and micro crack, but also produces serious wear behaviors such as matrix peeling and diamond peeling.

Keywords

• c/sic ceramic matrix composite
• brazed diamond abrasive drill
• chip
• axial drilling force
• drill wear