Dynamic and Static Fatigue of Silicate Glasses

Fatigue of silicate glasses was studied using both static and dynamic tests. Static fatigue data for acid‐etched soda‐lime silicate glass determined at 74°F in 50 and 100% rh can be represented by a single universal fatigue curve (UFC). The UFC for acid‐etched glass does not lie on the UFC of Mould and Southwick, which was determined for abraded soda‐lime silicate glass; the acid‐etched glass was less susceptible to static fatigue. The susceptibility of acid‐etched soda‐lime silicate glass to static fatigue differed little from that of pristine E‐glass and fused SiO 2 fibers. Dynamic fatigue data for soda‐lime, E, borosilicate, and fused quartz glasses agreed well qualitatively and quantitatively with fundamental crack velocity data for these glasses; the dynamic fatigue theory of Charles was used in the comparison. The theoretical implications of these results are discussed.