LOCAL ELASTIC-PLASTIC RESPONSE OF WELDING JOINTS OF DOMEX700MS STEEL

Abstract

The paper deals with degradation of the structural and mechanical parameters of DOMEX 700MC steel due to welding process. It is focused on evaluation of the mechanical heterogeneities influence at higher strain rate. DOMEX 700MC presents the microalloyed steel with the increasing utilization mainly for the lightweight construction of the transportation means. The precise characterization of material behavior at high strain rate is of great importance for reliable prediction of welded parts in that application. Evaluation of the local mechanical parameters of experimental welding joints was performed. The three-point instrumented dynamic fracture analyses and instrumented indentation tests were employed to study the elastic-plastic response of critical weldments sublayers. The static vs. dynamic yield strength and energy consumption to fracture was compared in different stages of temper influence. Structural analyses brought the information about the conducted structural changes in tempered zone. Fractography analyses were focused on evaluation of local differences in fracture behavior influenced by real metallurgy quality. Based on the experimental results, the used combination of loading method is suitable to determine the local mechanical properties and enable the estimation of temper sensitivity of analyzed steel.