Two-parameter J-A concept in connection with crack-tip constraint. (December 2017)

• Record Type: Journal Article
• Authors: Matvienko, Yu.G.; Nikishkov, G.P.
• Is Part Of: Theoretical and applied fracture mechanics. Volume 92(2017)
• Page Start: 306
• Page End: 317
• Publication Date: 2017-12
• Subjects: Three-term elastic-plastic asymptotic expansion -- J-A fracture criterion -- Finite element method -- Crack-tip constraint parameters; Fracture mechanics -- Periodicals; 620.1126
• DOI: 10.1016/j.tafmec.2017.04.007
• Languages: English
• ISSNs: 0167-8442

Abstract

Highlights: Two-parameter J - A approach in elastic-plastic fracture mechanics is discussed. The constraint parameter A for various configurations of specimens is computed. The unified JC - A master curve is constructed. Relationship between the crack-tip constraint parameters is analyzed. Abstract: The paper presents theoretical and numerical aspects of the two-parameter J - A approach in elastic-plastic fracture mechanics in connection with crack-tip constraint. This approach is based on the three-term asymptotic expansion for the stress field near the tip of mode I crack in an elastic-plastic solid. It is shown that the parameter A can be introduced in fracture criterion as a constraint parameter. The constraint parameter A and the J -integral for various configurations of standard specimens and the hardening exponent is computed by means of three-dimensional elastic-plastic stress analyses employing finite element method. The magnitude of the constraint parameter A decreases (higher constraint) with the increase of relative specimen thickness. The unified JC - A master curve is constructed for different geometry and thickness of specimens. The two-parameter J - A fracture criterion allows estimating whether elastic approach is conservative or non-conservative. Relationship between the crack-tip constraint parameters A, A 2, Q and S ¯ p of elastic-plastic fracture mechanics is investigated.