Due to local uneven heating during the welding process,the residual stress of the structure after welding affects the reliability of it.In order to ensure the reliability,it is of great significance to test the residu...Due to local uneven heating during the welding process,the residual stress of the structure after welding affects the reliability of it.In order to ensure the reliability,it is of great significance to test the residual stress distribution of the welded joint.It has always been the focus to find a simple and feasible method for residual stress testing to quickly and accurately obtain the residual stress distribution of welded joints.The mechanical measurement method has high measurement accuracy,convenient and easy operation,but it will cause certain damage to the components.Physical measurement method can avoid damage to components,but its test cost is usually high,and its measurement accuracy can also be affected by the material microstructure characteristics of welded components.Based on the advantages and disadvantages of these two residual stress test methods,a modal test method is proposed.This method is a non-destructive measurement method.Based on the mathematical relationship between the residual stress of the welded structure and the natural frequency(mathematical model),the natural frequency is measured through the modal test to calculate the residual stress quickly.However,it is difficult to establish a mathematical model with this method,and it is not suitable for realization.展开更多
超窄间隙激光填丝焊(Ultra-narrow gap laser welding,Ultra-NGLW)是一种先进的厚贝氏体钢焊接技术。通过数值模拟和X射线衍射法,分析了超窄间隙激光填丝焊接头残余应力的分布和变化,结果表明:在不同厚度(20,50,70 mm)的超窄间隙激光填...超窄间隙激光填丝焊(Ultra-narrow gap laser welding,Ultra-NGLW)是一种先进的厚贝氏体钢焊接技术。通过数值模拟和X射线衍射法,分析了超窄间隙激光填丝焊接头残余应力的分布和变化,结果表明:在不同厚度(20,50,70 mm)的超窄间隙激光填丝焊接头的表面,残余应力均呈"W"形分布。利用微型剪切试验,分析了显微组织对接头残余应力的影响:熔合线处形成的马氏体脆硬组织使接头形成了"软-硬-软"的夹心组织,导致接头的应力分布与一般的焊接接头不同,而多层填丝焊的特殊工艺导致接头中间层的应力增加。展开更多
基金Project was supported by the National Natural Science Foundation of China(Grant No.52165034)Science and Technology Programs of Inner Mongolia(Grant No.2020GG0301)+1 种基金Natural Science Foundation of Inner Mongolia Autonomous Region(Grant No.2019MS05061)Scientific Research Projects of Higher Education of Inner Mongolia Autonomous Region Institutions(Grant No.NJZY20066).
文摘Due to local uneven heating during the welding process,the residual stress of the structure after welding affects the reliability of it.In order to ensure the reliability,it is of great significance to test the residual stress distribution of the welded joint.It has always been the focus to find a simple and feasible method for residual stress testing to quickly and accurately obtain the residual stress distribution of welded joints.The mechanical measurement method has high measurement accuracy,convenient and easy operation,but it will cause certain damage to the components.Physical measurement method can avoid damage to components,but its test cost is usually high,and its measurement accuracy can also be affected by the material microstructure characteristics of welded components.Based on the advantages and disadvantages of these two residual stress test methods,a modal test method is proposed.This method is a non-destructive measurement method.Based on the mathematical relationship between the residual stress of the welded structure and the natural frequency(mathematical model),the natural frequency is measured through the modal test to calculate the residual stress quickly.However,it is difficult to establish a mathematical model with this method,and it is not suitable for realization.
文摘超窄间隙激光填丝焊(Ultra-narrow gap laser welding,Ultra-NGLW)是一种先进的厚贝氏体钢焊接技术。通过数值模拟和X射线衍射法,分析了超窄间隙激光填丝焊接头残余应力的分布和变化,结果表明:在不同厚度(20,50,70 mm)的超窄间隙激光填丝焊接头的表面,残余应力均呈"W"形分布。利用微型剪切试验,分析了显微组织对接头残余应力的影响:熔合线处形成的马氏体脆硬组织使接头形成了"软-硬-软"的夹心组织,导致接头的应力分布与一般的焊接接头不同,而多层填丝焊的特殊工艺导致接头中间层的应力增加。