Fatigue Limit In Borosilicate Glass By Interrupted Static Fatigue Test

The threshold stress intensitiy factor, Kth, for sub-critical crack growth of borosilicate glass was measured in water environment using the interrupted static fatigue test. Bending tests with durations ranging from 1h to 50 days were performed. Around 15 specimens were tested at each condition and the constant stress applied varied from 70 to 95 MPa. The stress intensity factor, Kw, applied to the weakest surviving sample during the stress hold was calculated as a function of the dwell time.