Investigation on the constraint effect on the fracture toughness assessment of stainless steel AISI 304L thin sheets

Abstract

The aim of the study is to assess the constraint effect induced by variation of geometric parameters on fracture toughness of stainless steel 304L thin sheets. A combined experimental-computational method is used. Compact Tension (CT) tests are firstly done using a special device realized to avoid buckling problems. Finite element analysis is used including the GTN (Gurson-Tvergaard-Needleman) model based on micromechanical assumptions of ductile fracture to obtain crack propagation. The fracture toughness is evaluated using an incremental formulation of the J-Integral. The results obtained show a quantified dependency of the critical fracture toughness on the constraint effect.