This study investigates Q960 ultrahigh-strength steel as the research object.Based on software,a thermo-metallurgical-mechanical finite element model(FEM)is established to simulate the welding temperature field and re...This study investigates Q960 ultrahigh-strength steel as the research object.Based on software,a thermo-metallurgical-mechanical finite element model(FEM)is established to simulate the welding temperature field and residual stress distribution.At the same time,the hole-drilling(HD)method is used to measure the residual-welding stress distribution on the surface of the single-pass.Numerical simulation and experimental results show that the predicted value of numerical simulation agrees well with the experimentally measured value,which verifies the accuracy of the FEM.Based on the verification model,the surface and internal stress distribution characteristics of Q960 ultrahigh-strength steel during the multipass remelting of Q960 ultrahigh-strength steel considering solid-state phase transformation(SSPT)are analyzed.The results show that when SSPT is considered,after single-pass welding of Q960 ultrahigh-strength steel,the welded joint is dominated by tensile residual stress,and the peak stress is located in the heat-affected zone(HAZ).At the same time,the effect of SSPT can significantly reduce the size of the residual stress in the weld and affect the distribution of the lateral residual stress.Additionally,as the number of weld passes increased,the transverse residual stress at the center of the weld showed a“stepped”trend,and a local compressive stress peak appeared at the location of the HAZ.展开更多
随着工程机械市场的发展,客户对产品外观质量要求也越来越高,而CO_2气体保护焊存在焊接飞溅大、焊缝成形较差等问题,影响了工程机械结构件的质量,富氩CO_2气体保护焊与CO_2气体保护焊相比,具有焊缝表面成形好、飞溅少、低温冲击韧性和...随着工程机械市场的发展,客户对产品外观质量要求也越来越高,而CO_2气体保护焊存在焊接飞溅大、焊缝成形较差等问题,影响了工程机械结构件的质量,富氩CO_2气体保护焊与CO_2气体保护焊相比,具有焊缝表面成形好、飞溅少、低温冲击韧性和抗疲劳性能好的特点。针对某工程机械企业所用Q960级钢板进行了热输入为7.0 k J/cm的富氩CO_2焊斜Y坡口焊接裂纹试验和热输入为(8.0±1) k J/cm的富氩CO_2焊焊接工艺试验,结果表明:采用富氩CO_2焊焊接宽厚板时,厚板多层焊根部焊道的冷裂纹敏感性好,而拉伸与弯曲试验表明,不是所有的Q960级宽厚板材都适合采用富氩CO_2焊的焊接方法。展开更多
文摘This study investigates Q960 ultrahigh-strength steel as the research object.Based on software,a thermo-metallurgical-mechanical finite element model(FEM)is established to simulate the welding temperature field and residual stress distribution.At the same time,the hole-drilling(HD)method is used to measure the residual-welding stress distribution on the surface of the single-pass.Numerical simulation and experimental results show that the predicted value of numerical simulation agrees well with the experimentally measured value,which verifies the accuracy of the FEM.Based on the verification model,the surface and internal stress distribution characteristics of Q960 ultrahigh-strength steel during the multipass remelting of Q960 ultrahigh-strength steel considering solid-state phase transformation(SSPT)are analyzed.The results show that when SSPT is considered,after single-pass welding of Q960 ultrahigh-strength steel,the welded joint is dominated by tensile residual stress,and the peak stress is located in the heat-affected zone(HAZ).At the same time,the effect of SSPT can significantly reduce the size of the residual stress in the weld and affect the distribution of the lateral residual stress.Additionally,as the number of weld passes increased,the transverse residual stress at the center of the weld showed a“stepped”trend,and a local compressive stress peak appeared at the location of the HAZ.
文摘随着工程机械市场的发展,客户对产品外观质量要求也越来越高,而CO_2气体保护焊存在焊接飞溅大、焊缝成形较差等问题,影响了工程机械结构件的质量,富氩CO_2气体保护焊与CO_2气体保护焊相比,具有焊缝表面成形好、飞溅少、低温冲击韧性和抗疲劳性能好的特点。针对某工程机械企业所用Q960级钢板进行了热输入为7.0 k J/cm的富氩CO_2焊斜Y坡口焊接裂纹试验和热输入为(8.0±1) k J/cm的富氩CO_2焊焊接工艺试验,结果表明:采用富氩CO_2焊焊接宽厚板时,厚板多层焊根部焊道的冷裂纹敏感性好,而拉伸与弯曲试验表明,不是所有的Q960级宽厚板材都适合采用富氩CO_2焊的焊接方法。
