Study of carbon-fiber-reinforced-polymer under moderate laser intensity. Application to laser drilling

Carbon-fiber-reinforced polymers are increasingly used especially in structural parts for new aircraft. However, laser machining is not well implemented for cutting or drilling because significant collateral effects remain. We study laser-matter interaction at moderate laser intensity (<1MW/cm²) of CFRP. The dynamic of the process is observed by high speed camera (30 000 img/s). It shows a rapid evaporation of the matrix which produced the mechanical rupture and the ejection of carbon fibers. Drilling velocity measurements are also performed. They show that drilling velocity increases with laser intensity. The residual state of matter is also observed as a function of laser parameters showing that a deeplier damage along the direction of fiber.