Fracture Mechanics

1983 ◽  
pp. 269-293
Author(s):  
R. L. Tobler ◽  
H. I. McHenry
Keyword(s):  
Fracture Mechanics ◽  
Crack Opening Displacement ◽  
Low Temperatures ◽  
Fracture Behavior ◽  
Crack Opening ◽  
J Integral ◽  
Cryogenic Temperatures ◽  
Testing Methods ◽  
Opening Displacement ◽  
The Many

Abstract This chapter reviews the concepts of fracture mechanics and their application to materials evaluation and the design of cryogenic structures. Emphasis is placed on an explanation of technology, a review of fracture mechanics testing methods, and a discussion on the many factors contributing to the fracture behavior of materials at cryogenic temperatures. Three approaches of elastic-plastic fracture mechanics are covered, namely the crack opening displacement, the J-integral, and the R-curve methods. The chapter also discusses the influence of thermal and metallurgical effects on toughness at low temperatures.

The Relationship Between Stress Intensity Factor, Crack Opening Displacement and J-Integral in Zr-2.5 Percent Nb

1980 ◽  
Vol 102 (1) ◽  
pp. 97-100 ◽  
Author(s):  
L. A. Simpson
Keyword(s):  
Stress Intensity ◽  
Crack Opening Displacement ◽  
Crack Extension ◽  
Crack Opening ◽  
J Integral ◽  
Opening Displacement ◽  
Crack Face ◽  
Critical Crack ◽  
Wide Range ◽  
The Relationship

Crack opening displacement (COD) has been determined in Zr-2.5 percent Nb over a wide range of applied stress intensity, K. Prior to initiation of crack extension, COD was determined from measurements of stretch zones in specimens which had undergone hydrogen-induced, sub-critical crack growth. In post initiation measurements (during slow stable crack extension), COD was determined from crack face displacement. Both methods were self consistent and depended on the plastic-zone-corrected K in accordance with the Wells equation. The J-integral was also determined during stable crack extension using the method of Garwood, et al. The results are consistent with the COD measurements based on theoretical relationships between the two crack tip parameters.

Sign in / Sign up

Export Citation Format

Share Document