Surface damage resistance and yielding of chemically strengthened silicate glasses: From normal indentation to scratch loading

We report on surface elasticity, plastic deformation and crack initiation of chemically strengthened soda-lime silicate sodium aluminosilicate glasses during lateral indentation scratch testing. Instrumented using a normal indenter set-up corroborated previous findings the effects chemical strengthening Young's modulus, hardness, cracking. Using in elastic-plastic regime, we find pronounced increase hardness as result strengthening, manifest higher work required for creating groove. Thereby, glass composition is found to play stronger role than absolute magnitude compressive stress. blunt conical stylus instrumented testing reveals three distinct modes scratch-induced fracture, which occur scratching or after unloading. Occasional micro-cracking caused by pre-existing flaws at low load can be completely suppressed through strengthening. The intrinsic defect resistance microcracking reduced ion stuffing, depending initial composition, whereas abrasive yielding enhanced several hundred MPa.