Indentation Determination Of Fatigue Limits In Silicate Glasses

An experimental approach has been used to measure the threshold stress intensity factor (Kth) for subcritical crack growth in brittle materials using indentation cracks. The data show that Kth values existed in soda-lime-silica and soda-alumina-silica glasses that were tested in a neutral aqueous environment. For the former glass, tests also were performed in acidic and basic solutions. A threshold for subcritical crack growth was observed for acidic conditions but not for alkaline conditions.