FRACTURE STRENGTH OF LASER ETCHED GLASS

The effect of CO2 laser etching on the strength of soda lime plate glass has been investigated. The majority of common beverage glassware is comprised of soda lime glass. Laser etching is used to create patterns on such glassware for aesthetic reasons. Various etching conditions have been investigated in order to compare to the strength of un-etched glass. Three point bend tests were used to determine strength values. The resulting fracture strength of etched glass is based upon the flaws and resulting stress concentrations created during the laser ablation process. In addition to stress concentrations, the thermal history and residual thermal stresses play a role in the failure process. Samples were also cyclically washed to determine the effect of water and thermal cycling. Results were documented and compared via Weibull analysis. Nominal strength values were 114 MPA for unetched, 83 MPa for wash cycled, 43 MPa for etched, and 33 MPa for etched and wash cycled.