Abstract
Polycarbonate (PC) is one of the widely used materials for headlamp lens application in automobiles. Although the parent material is ductile exhibiting plastic strains of the order of 120 percent, the headlamp used in the vehicle has exhibited failure at significantly less plastic strains repeatedly during head impact tests, which are part of the pedestrian protection load cases. There could be several reasons for this reduction in failure strain – processing and manufacturing factors, stress state during deformation, strain rate dependency to name a few. This work investigates the effect of coating and manufacturing processes on the yield, post yield and failure behavior of PC material under quasi-static loading while varying the process parameters such as (i) coating, (ii) injection molding/ water jet cutting and type of testing standard. Water-jet cutting is found to have maximum impact on reduction of failure strain although coating and specimen size also have some effect.