多重?zé)嵫h(huán)和約束條件對(duì)P92鋼焊接殘余應(yīng)力的影響多重?zé)嵫h(huán)和約束條件對(duì)P92鋼焊接殘余應(yīng)力的影響INFLUENCE OF MULTI-THERMAL CYCLE AND CONSTRAINT CONDITION ON RESIDUAL STRESS IN P92 STEEL WELDMENT 本文系統(tǒng)地研究了P92鋼板在經(jīng)受多重?zé)嵫h(huán)的作用下，焊接殘余應(yīng)力的演化過(guò)程與形成機(jī)理?；赟YSWELD有限元軟件，開發(fā)了考慮“熱-冶金-力學(xué)”耦合的計(jì)算方法，數(shù)值模擬了Satoh試驗(yàn)和兩道重熔平板接頭的應(yīng)力場(chǎng)。在數(shù)值模擬中，詳細(xì)考慮了固態(tài)相變引起的體積變化、屈服強(qiáng)度變化和相變塑性對(duì)殘余應(yīng)力形成過(guò)程的影響。同時(shí)，采用了盲孔法和X射線衍射(XRD)法測(cè)量了P92鋼兩道TIG重熔的平板接頭殘余應(yīng)力分布。計(jì)算結(jié)果和實(shí)驗(yàn)結(jié)果表明兩者吻合較好，驗(yàn)證了所采用的計(jì)算方法的有效性和準(zhǔn)確性。模擬結(jié)果表明，P92鋼兩道重熔平板接頭的縱向殘余應(yīng)力呈現(xiàn)出清晰的拉-壓相間分布形態(tài)。每道焊縫及其熱影響區(qū)(HAZ)的縱向殘余應(yīng)力為壓應(yīng)力，HAZ外側(cè)附近產(chǎn)生了較大的縱向拉應(yīng)力。此外，本研究還采用數(shù)值模擬方法探究了橫向拘束對(duì)焊接殘余應(yīng)力的影響，數(shù)值模擬結(jié)果表明，橫向約束可以明顯降低橫向殘余應(yīng)力，特別是焊縫端部的應(yīng)力峰值。 The evolution and formation mechanism of welding residual stress in P92 steel joint under multiple thermal cycles were investigated in the current study. Based on SYSWELD software, a computational approach considering the couplings among thermal, micro-structure and mechanics was developed to simulate welding residual stress in P92 steel joint. Using the developed computational tool, the evolution of residual stress in Satoh test specimen was studied, and welding residual stress distribution in double-pass welded joint was calculated. In the numerical models, the influences of volume change, yield strength variation and plasticity induced by phase transformation on welding residual stress were taken into account in details. Meanwhile, the hole-drilling method and X-ray method were employed to measure the residual stress distribution in the double-pass welded joint. The simulated results match the experimental measurements well, and the comparison between the measurements and the predictions suggests that the computational approach developed by the current study can accurately predict welding residual stress in multi-pass P92 steel joint. The simulated results show that the longitudinal residual stress distribution around the fusion zone has a clear tension-compression pattern. Compressive longitudinal residual stresses generated in the fusion zone and heat affected-zone (HAZ) of each pass, while tensile stresses produced near the HAZs. In addition, the numerical simulation also suggests that the transverse constraint has a large influence on the transverse residual stress, while it has an insignificant effect on the longitudinal residual stress. 全文下載：http://pan.baidu.com/s/1ccWEGQ
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