Abstract
Drilling experiments of CFRP/Ti6Al4V laminated stack board were carried out using of a TiN/AlN-coated cemented carbide drill and a TiAlCr/TiSi-coated cemented carbide drill. Under the experimental conditions described here, tool life was longer for lowered feed speed, and the TiAlCr/TiSi-coated cemented carbide drill had longer life than the TiN/AlN-coated cemented carbide drill. In addition, the cooling performance between dry process and water-mist-cooling were compared. The thrust and error of the hole diameter were both smaller for water-mist-cooling. Water-mist-cooling reduced tool abrasion for hole numbers of less than 100. However, the abrasion increased suddenly for hole numbers greater than 100 as in drilling at colder temperatures by water-mist-cooling, the chip may not curl and adhere to the drill.
