Effects of weld metal strength and transformation temperature on welding residual stress

Abstract

In this study, we assess the effects of weld metal strength and transformation temperature on the residual stress in 2?25Cr-1?6W steel welded joints. We find that the stress levels in the weld and the peak residual stress position in the base metal can be controlled by the appropriate selection of filler metal. Low transformation temperature weld metals are capable of inducing compressive residual stresses in the weld bead. Meanwhile, for stresses and bending moment equilibrium, the high strength weld metal pushes the peak tensile stress outward to reside at the base metal, keeping off the weak region. A reasonable agreement is obtained between the numerical modelling considering phase transformation and the accurate local stresses measurement associated to weld microstructure regions.

Influence of alloy type, peak temperature and constraint on residual stress evolution in Satoh test

“…This observation matches the reported behaviour of single pass laser welds, such as in Ref. 18 where the highest welding residual stresses are in a location in the HAZ, removed from the fusion line and consistent with a T p vAc 1 .…”

Tensões Residuais em Soldagem a Arco: Uma Visão Holística

“…Por exemplo, Deng e Murakawa (2006) observaram que quando o efeito de transformação martensitica foi incluso no modelo numérico de soldagem de topo de um aço ao carbono martensitico, as tensões residuais axiais na ZF invertem o seu sinal quando comparado com o modelo onde somente a alteração do limite de escoamento foi considerado. Xu et al (2015) observaram que no aço microligado de alta resistência, as TR de tração podem passar a ser de compressão devido a transformação bainitica na ZAC durante o resfriamento após soldagem. Entretanto, Xu et al alertam para que se a temperatura de transformação martensitica não for baixa suficiente, a compressão induzida por transformação não será suficiente para aniquilar a tensão de tração devido a contração térmica e ao final do resfriamento as TR permanecem trativas.…”

Metallurgical effects and distortions in laser welding of thin sheet steels with variations in strength

“…The connection between distortion and parameters such as heat input, resulting microstructure in weld metal and HAZ, weld width and hardness is not clear. It has been claimed, though, that the energy density distribution of the heat source [8], the cross-sectional geometry and microstructure [9][10][11][12], volume change due to martensite formation [13] and heat affected zone microstructure [14] are all factors that influence the distortions.…”