Limit load based evaluation of plastic η factor for C(T) specimen with a mismatched weld

摘要

Plastic η factor is adopted to account crack tip plasticity while evaluating the fracture toughness of the materials as per ASTM E1820. It is valid only for homogeneous materials. The plastic η factor for compact tension geometry (CT) with type 316LN stainless steel weld has been evaluated based on elastic-plastic FE analysis. The incremental elastic-plastic material model with various values for strength mismatch level ( M ), from 1.2 to 2.2 has been considered for the weld. The weld width ( h ) parallel to the crack plane is varied from 4 mm to 16 mm. The η values thus obtained are analyzed and the inferences are discussed. ? Keywords: Limit load, Plastic η , elastic-plastic, strength mismatch level.