振动时效处理和消应力热处理对304L不锈钢焊接残余应力的影响

Influence of Vibration Aging Treatment and Stress Relief Annealing on Welding Residual Stress of 304L Stainless Steel

奥氏体不锈钢在腐蚀性介质中工作时,若焊接接头存在残余应力易产生应力腐蚀裂纹,需进行消应力处理。文中对不同的消应力方法及其组合对304L不锈钢焊接接头残余应力的影响进行了试验研究。结果表明,单纯的消应力热处理方式和进行机械振动时效处理均可有效去除焊缝及焊趾的峰值应力,应力峰值下降相当,采用消应力热处理方式消应力相对比较均匀;采用振动时效+消应力热处理的方式与单纯的振动时效处理相比,应力峰值下降不明显,与先退火后振动时效相比,焊缝处应力峰值略有下降;采用消应力热处理+振动时效的方式,相比较单纯消应力热处理应力峰值下降明显。

When austenitic stainless steel works in corrosive medium, it is easy to generate stress corrosion crack if residual stress exists in welded joint, so stress relief treatment is needed. The influence of different stress relieving methods and their combinations on residual stress of 304 L stainless steel welded joint are studied experimentally. The results show that both the simple stress relief annealing method and the mechanical vibration aging treatment can effectively relieve the peak stress of the weld and weld toe, the stress peak drops are equivalent, and the stress relief annealing method relieves stress more uniformly. Compared with the simple vibration aging treatment, the decrease of stress peak of vibration aging + stress relief annealing method are not obvious, compared with the vibration aging after the first annealing, the stress peak of the weld reduces slightly. Compared with the simple stress relief annealing method, the stress relief annealing + vibration aging method results in a significant decrease in the stress peak.