Study into causes of damage to carbon epoxy composite material during the drilling process

Abstract

There is increasing interest from industry in the machining of composite materials, especially the drilling of thick composite panels and of multi-material assemblies. Damage to laminates due to drilling has an influence on the resistance of plates to the various stresses applied to the structure. The present paper aims firstly to highlight the different defects generated by drilling thick carbon epoxy plates at the entry, on the wall and on the whole exit. Following this, the main aim of this work is the observation in the real time of the initiation and the propagation of such defects. This enables to understand and to show the causes of these defects and then allow operating procedures to be proposed that are likely to reduce such damage.