TY - CONF A1 - Welter, T. A1 - Nofz, Marianne A1 - Deubener, Joachim T1 - Surface water-induced broadening of crack initiation probability of zinc aluminosilicate glasses N2 - The crack generation probability by Vickers indentation of glass surfaces is known to be influenced by the atmospheric conditions under which the Vickers experiment is performed [1]. However, the effect of surface water due to preparation and storage of the glass surfaces prior to the indentation is less understood. Therefore, zinc aluminosilicate glasses of perzinc, peraluminous as well as nominally NBO-free meta-aluminous composition were prepared by melt quenching. Surfaces of cut and polished specimens of these glasses were either stored for seven days under constant atmosphere (50 °C; 55% RH) or etched (HF: 20vol%; 20 min) shortly before indentation. The obtained results show a strong variation of crack initiation behavior depending on chemical composition of the glasses as well as sample preparation. All experiments were performed in dry nitrogen gas to minimize the influence of atmospheric humidity during indentation. While the regular glass surfaces exposed to humid air prior to Vickers indentation show a broad distribution of crack initiation probability, this distribution narrows down if etched glass surfaces are tested. SNMS depth profiling shows a water enriched layer at the surface (150 μm) for the non-etched and stored specimens leading to the conclusion that surface water causes broadening of the crack initiation probability of glass surfaces. T2 - 91. Glastechnische Tagung CY - Weimar, Germany DA - 29.05.2017 KW - Aluminosilicate glasses KW - Crack initiation probability KW - Surface water KW - Vickers indentation PY - 2017 AN - OPUS4-44379 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -