Volume 26, Issue 5 (September 1998)
A Computer Program to Aid in Fatigue Precracking of Fracture Toughness Test Specimens
Fatigue precracking prior to fracture toughness and fatigue tests ensures a sharp crack ahead of the notch tip. The precracking procedure is outlined in ASTM Standards E 399-78a (Standard Test Method for Plane-Strain Fracture Toughness of Metallic Materials). E813-89 (Standard Test Method for JIC, A Measure of Fracture Toughness), and E-1152-87 (Standard Test Method for Determining J-R Curves). This paper describes an interactive computer program that accepts material properties and specimen dimensions as program input. The program output when plotted graphically suggests an easy and practical precracking procedure adhering to the standards mentioned above. The program is useful in the absence of a computer-controlled testing facility. The program listout is given in the Appendix.