Accession Number:

ADA243568

Title:

Dynamic Measurement of the J Integral in Ductile Metals: Comparison of Experimental and Numerical Techniques

Descriptive Note:

Corporate Author:

CALIFORNIA INST OF TECH PASADENA GRADUATE AERONAUTICAL LABS

Personal Author(s):

• Zehnder, Alan T.
• Rosakis, Ares J.
• Krishnaswamy, Sridhar

Report Date:

1988-08-01

Pagination or Media Count:

42.0

Abstract:

For two-dimensional, monotonically loaded, stationary cracks, the J integral, defined by Rice is a path independent line integral over an open contour surrounding the crack tip, and its value is a measure of the intensity of the crack tip strain singularity. The critical value of J for crack initiation is commonly used as a measure of fracture toughness in ductile materials. For three dimensional plates of uniform thickness containing through cracks, the J integral is defined over a cylindrical surface surrounding the entire crack front. For monotonic loading or for materials obeying the deformation theory of plasticity, the value of this integral is independent of the choice of surface. In addition, for materials obeying the deformation theory of plasticity this integral may be interpreted as the energy release rate for self-similar crack extension along the entire crack front. A per thickness value, denoted in the rest of the paper as J, can be obtained by dividing the above surface integral by the thickness of the plate.

Descriptors:

• *LINEAR SYSTEMS
• MEASUREMENT
• THICKNESS
• DYNAMICS
• MATERIALS
• DEFORMATION
• CRACKING(FRACTURING)
• CRACKS
• INTEGRALS
• THEORY
• PATHS
• RATES
• TOUGHNESS
• ENERGY TRANSFER
• FRACTURE(MECHANICS)
• SURFACES
• THREE DIMENSIONAL
• CYLINDRICAL BODIES
• PLATES
• PLASTIC PROPERTIES
• DUCTILITY
• NUMERICAL METHODS AND PROCEDURES
• PAPER
• J INTEGRALS
• METALS

Subject Categories:

• Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE