極厚板의 EGW 및 FCAW에 대한 熔接部의 力學的 特性에

Abstract

Recently, a steel structure in industry becomes a larger structure and consequently an application of ultra thickness plate of the high-tensile is augmented. An application of ultra thickness plate increase man-hours, therefore multi-layer welding FCAW(Flux Cored Arc Welding) substitutions of existing, applies 1Pole EGW(Electro Gas Welding) processes from below steel thick 55mm and above of 55mm 1Pole EGW processes and FCAW processes and 2Pole EGW process high efficiency substitution line welding process are become accomplished for an improvement of welding productivity However, EGW process affect big in physical properties of the base metal and the welding material, differently the multi-layer welding(FACW). The welding of ultra thickness plate by EGW as well as limited heat input and a heat treatment after welding is required, for reduce a brittle fracture due to an overdose heat input. Due to fracture toughness and fatigue life decreased in accordance with highly heat input welding process on an ultra thickness plate. As some outside Classification (NK, GL) used in steel thickness (65mm or more) questions about filed with the relevant provisions and measures to enhance fracture toughness and CTOD (Crack Tip Opening Displacement) or Kca (Crack Arrest Ability) design standards for the destruction is required. However, considering the domestic case of brittle fracture of ultra thickness plate established criterion are not applied, as well as the theoretical and experimental research on the effectiveness and the very lack of systematic research is considered. Thus, for a highly heat input welding in ultra thickness plate performance and mechanical behavior of materials phenomena, by examining the safety and reliability in welding, as well as urgent response, called the plan will prepare.

In this study, a high-strength ultra thickness EH36-TMCP steel by highly heat input welding process In this study, a high strength ultra thickness EH36-TMCP steel highly heat input welding process applied to EGW, A weld reliability and suitability, to ensure endurance, the heat of welding and welding residual stresses due to temperature changes and the prediction of residual stress and its impact on the destructive behavior was identified, as well as conventional multi-layer welding FCAW weld characteristics and differences comparisons, were reviewed.