Perfis de tensão residual do aço duplex UNS S32304 submetido à processo de soldagem TIG e diferentes condições de tratamento térmico de tempera

Abstract

Structural failures can occur by a service and residual stressescombination effects. These are generated on the material after the non-uniform plastic deformation originated by mechanical, thermal or chemical process. In this work, the residualstresses mean valuesare investigated by X ray diffraction technique. Samples of duplex stainless steel UNS S32304 subjected to different heat treatment conditions and TIGwelding process are used. From the total mean stress values the residual stress profiles are obtained. This was possible by the 420 austenite plane behavior analysis with CuKαradiation (ߣ̅= 0.1542nm) and the 211 ferrite plane analysis with CrKαradiation (ߣ̅= 0.2291 nm). The samples were heat treated at475 °C, 600 °C and 750 °C for 8 hat air atmosphere and cooled in sea water. The results were analyzed by the sen²ψmethod and indicate that the thermal and microstructural variations related to different experimental conditionschange thematerial total mean residual stresses and consequently the stress profile