Estudo das tensões residuais de juntas soldadas de aço API 5L X80

Abstract

Resumo Este trabalho teve por objetivo determinar os níveis de tensões residuais decorrentes de processos de soldagem em juntas soldadas tensões residuais trativas na região do Metal de Solda (MS) e menor foi o nível de tensões residuais trativas na Zona Termicamente Afetada (ZTA). Palavras-chave: Aço API 5L X80, Juntas soldadas, Tensões residuais, Difratometria de raios-x.Abstract: This study aimed to determine the levels of residual stresses due to welding processes in welded joints of API 5L X80 steel. Initially were executed the welded joint using the Shielded Metal Arc Welding (SMAW) and Gas Tungsten Arc Welding (GTAW) processes, with different consumables and employing an interpass temperature of 175ºC. Three different welded joints were obtained. The residual stress measurements were carried out by x-ray diffraction using a portable diffractometer and software for analyzing the results. In the upper region, it was observed that to higher heat inputs the residual stresses levels were more compressive and more displaced were the tensile stresses peaks. In the lower region of the welded joints, it was found that for higher heat input, were higher levels of tensile residual stresses in the region of the Weld Metal (WM) and the lower the level of tensile residual stresses in the Heat Affected Zone (HAZ).