STP791: A Perspective on R-Curves and Instability Theory

    McCabe, DE
    Senior engineer, Westinghouse Research and Development Center, Pittsburgh, Pa.

    Ernst, HA
    Senior engineer, Westinghouse Research and Development Center, Pittsburgh, Pa.

    Pages: 24    Published: Jan 1983


    Abstract

    Several aspects of elastic-plastic R-curve theory and instability analysis are discussed. It is shown how material flow property effects can be incorporated into the R-curve in place of the more common practice of incorporation into J crack drive. Formulas for deformation theory J that adjust for slow-stable crack growth in compact (CT) and center cracked tension (CCT) specimens are presented. For cases of extremely large crack extension where conditions of deformation theory J are violated, an expression for modified J also is presented. JR-curve data obtained from a 4T size compact specimen were used to predict instability in a displacement controlled CCT test for 2024-T351 aluminum.

    Keywords:

    R-curve, elastic-plastic fracture, J-integral, fracture mechanics, crack propagation


    Paper ID: STP37094S

    Committee/Subcommittee: E08.08

    DOI: 10.1520/STP37094S


    CrossRef ASTM International is a member of CrossRef.