Experimental study on glass edge machining flaw characterization

• Characterization of glass edge machining flaws.
• Comparison of 5 edge finishings and 7 manufacturing suppliers.
• Experiments analyzed using fracture mechanics and strength-related parameters.
• Provide a link between flaws detected with a microscope and strength values from bending tests.

Knowledge of failure strength is the key to structural glass applications. However, the influence of the manufacturing process on the failure initiation at the glass edge is not well known. For this paper, small-scale glass specimens are tested in four-point bending, creating tensile stresses at the glass edge. Several edge finishings are investigated and their flaws detected concentrating on the failure initiating flaw. The characteristics of glass edge machining flaws are estimated by comparing obtained experimental values to existing time-dependent strength theory described in fracture mechanics. As a conclusion, typical edge flaws in industrial glass edge finishings are characterized and used as a basis for glass failure strength estimations.