DYNAMIC AND STATIC FATIGUE OF SILICATE GLASSES,
  Report No. UM70-9, School of Engineering, University of Massachusetts, Amherst, MA, by John E. Ritter, Jr. and Charles L. Sherburne, December 1970, 84 pages.

Fatigue of silicate glasses was studied using both static and dynamic tests. Static fatigue data for acid-etched, soda-lime-silica glass determined at 74* F in atmospheres of 50 and 100% relative humidity could be represented by a single universal fatigue curve. The UFC for acid-etched glass does not lie on the UFC of Mould and Southwick which was determined for abraded soda-lime-silica glass, the acid-etched glass being less susceptible to static fatigue. On comparing the fatigue behavior of acid-etched, soda-lime-silica glass to that of pristine E-glass and fused silica fibers, little difference was found in the susceptibility to static fatigue. In addition, dynamic fatigue data for a wide variety of silicate glasses (soda-lime-silica, E-glass, Pyrex, and fused quartz) was compared to fundamental crack velocity data for these glasses utilizing the dynamic fatigue theory of Charles. Agreement was good on both a quantitative and qualitative level. The theoretical implications of these results on static and dynamic fatigue are discussed.