Stable Growth and Instability of Circumferential Cracks in Type 304 Stainless Steel Pipes Under Tensile Load

Abstract

Flaws due to stress corrosion cracking have frequently been found in Type 304 stainless steel piping of some boiling water reactor (BWR) plants. In this work, in order to quantitatively examine the integrity under the presence of such cracks, pipe fracture tests and related finite element analyses were conducted. The unstable fractures were observed under the quasi-static and the dynamic tensile loading conditions with a high-compliance test machine. The finite element methods were used to demonstrate the effectiveness of the J -integral and the crack tip opening angle (CTOA) as criteria for stable crack extension, and that of the total displacement stationariness condition as a criterion for the onset of instability.