Welding thermoplastic elastomers to polypropylene with a diode laser

Abstract

The process of welding thermoplastic elastomers to polypropylene using scanning transmission laser welding was studied. Thermoplastic rubber plaques of various durometers were welded to 30% glass-filled polypropylene using a 150 W diode laser. In transmission laser welding, one of the materials is transmissive to the laser and one absorbs the laser. In this study the elastomers were used as the transmissive material in some trials and as the absorbing material in others. Hence the polypropylene plaque was the absorbing material in the former trials and as the transmissive material in the latter. The effect of the laser welding parameters on weld quality, width and strength was studied. The laser welding parameters investigated were power, scanning speed, beam spot size, and clamp pressure. Weld strength was determined by tensile testing of the resulting shear lap samples. Implications of the effects of parameter changes on weld quality and on failure mode are discussed.