Accession Number : AD0743204

Title :   A Numerical and Experimental Investigation of the Use of J-Integrals.

Descriptive Note : Technical rept.,

Corporate Author : WASHINGTON UNIV SEATTLE DEPT OF MECHANICAL ENGINEERING

Personal Author(s) : Kobayashi,A. S. ; Chiu,S. T. ; Beeuwkes,R.

Report Date : MAY 1972

Pagination or Media Count : 30

Abstract : Finite element analysis was used to determine numerically Rice's J-integral values in centrally notched plates of 4340 steel. These numerical values were compared with corresponding J-integral values using Dugdale model and antiplane strain model with a power law hardening of n = 0.3. J-integral was also computed for a crack extending into its own plastic yield region under constant loading. For increasing level of loading, sigma, the rate of increase in J-integral decreases and J-integral remains almost constant at (sigma/(sigma sub ys)) = 1 under such crack extension. A limited number of fracture tests were conducted with centrally notched 4340 steel specimens heat treated to yield strength levels of 150, 180, 210 and 240 ksi. Fracture data showed that the critical J-integral, calculated and measured, is insensitive to crack tip sharpness for the lower strength 4340 material and thus the (J sub c) fracture criteria appears suited in correlating fracture data. (Author)

Descriptors :   (*STEEL, *FRACTURE(MECHANICS)), (*INTEGRALS, NUMERICAL INTEGRATION), CRACK PROPAGATION, STRESSES, ELASTIC PROPERTIES, NUMERICAL ANALYSIS, METAL PLATES

Subject Categories : Metallurgy and Metallography
      Numerical Mathematics

Distribution Statement : APPROVED FOR PUBLIC RELEASE