Acid‐Enhanced Crack Initiation in Glass

Abstract

Silicate glass rods containing Vickers indentations in the subthreshold‐fracture region can show dramatic strength losses on brief immersion in acid solutions. The effect is most significant for “normal” glasses, notably soda‐lime glass, and for HF‐based acids. After extended immersion the strength begins to recover, ultimately surpassing the original (pre‐immersion) level, as glass dissolution processes become dominant. The weakening effect is interpreted in terms of chemically enhanced residual‐contact stress effects.