Product Code: ICAL09_M602

A Comparison of Cut Path Deviation with Continuous and Pulsed Beam Modes in Diode Laser Chip-free Cutting of Glass
Authors:
Salman Nisar, The University of Manchester; Manchester Great Britain
Lin Li, The University of Manchester; Manchester Great Britain
M.A. Sheikh, The University of Manchester; Manchester Great Britain
Andrew J Pinkerton, The University of Manchester; Manchester Great Britain
Presented at ICALEO 2009

During laser cleaving of brittle materials with the controlled fracture technique, thermal stresses are generated. These induce the crack to form and extend it along the cutting path, which subsequently causes material separation. The fracture mechanism of cutting glass using a CO2 laser, where the laser beam is absorbed on the surface of the glass only, has been well studied, however in the case of a diode laser, where it is absorbed across the depth of the glass, little investigation has been performed. This paper reports a study on the effects of using a pulsed diode laser to cut soda lime glass. The work investigates the common problem of cut path deviation at the leading and the trailing edges of the glass sheet, which previous work has shown to be partly due the high magnitudes of thermal stresses generated. The effects of process parameters on the output variables of cut deviation angle and surface finish are experimentally determined and matched with finite element modelling simulations of the effects of the moving beam. The work shows how to minimise the cut path deviation at the edges of the sheet by reducing thermal stresses using optimum pulse diode laser parameters.