Abstract
An elastic/plastic finite element analysis was performed to provide insight into the minimum specimen size limitations for J characterization in large-scale yielding under a mixed-mode condition. The power-law hardening constitutive equation was employed and a plane strain condition was assumed. The criterion used to judge the degree of dominance was the extent of agreement of the stress field near the deformed crack tip with the results for the small-scale yielding. it was found that the ratio of the minimum ligament L to J/σ0 for the specimen under a mixed -mode condition necessary to ensure a J-based characterization is required to satisfy the next condition. L≧80J/σ0 for Mode I tensile specimen, L≧(8050)J/σ0 for Mode I tensile + Mode II Specimen and L≧50J/σ0 for Mode II specimen.
