Prediction of Ductile-to-Brittle Transition in Welded Joints with Strength Heterogeneity Subjected to Dynamic Loading(Brittle Fracture)

Abstract

Welded joint generally has heterogeneity of strength, material, and fracture toughness and it is important to understand the characteristics of material strength and fracture in welded joint considering heterogeneous effect. Furthermore, the material behavior becomes more complicated when welded joint received dynamic loading like as earthquake. Characteristics of strength and fracture in undermatched joint with strength heterogeneity by dynamic loading was studied by round-bar tension test and thermal elastic-plastic analysis in this paper. The strength and fracture in undermatched joints were evaluated by considering the effects of strain rate and temperature including temperature rise by dynamic loading. The differences of fracture characteristics like as ductile-to-brittle transition behavior are well precisely explained from the stress-strain distribution obtained by numerical analysis.