Relation between KIc and microscopic strength for low alloy steels

✍ Scribed by J.M. Alkin; A.S. Tetelman

• Publisher: Elsevier Science
• Year: 1971
• Tongue: English
• Weight: 831 KB
• Volume: 3
• Category: Article
• ISSN: 0013-7944
• DOI: 10.1016/0013-7944(71)90006-3

✦ Synopsis

A simple model has been developed to determine K~c in terms of the microscopic cleavage strength tr7 and the tensile yield strength trr for low temperature cleavage fracture in A302B and A533 reactor grade quenched and tempered steels. The model applies at sufficiently low temperatures or in irradiated steels where tr7 -< 3.4 try. It was determined that trt* is independent of temperature below -150°F and then increases with increasing temperature. At this time, it appears that tr* is independent of irradiation. At temperatures above that at which tr]~ _-< 3.4 try, unstable fracture initiates when a critical plastic strain ~y is achieved near to the crack tip. The critical local plastic strain for unstable fracture also increases with increasing temperature.