Author Name | Affiliation | Postcode | Changkun Wang* | School of Mechanical and Electronic Control Engineering, Beijing Jiaotong University, Beijing 100044, China China Railway Shanghai Design Institute Group Co., LTD., Shanghai 200070, China | 100044 | Huiyu Liu | School of Mechanical and Electronic Control Engineering, Beijing Jiaotong University, Beijing 100044, China | | Jiafei Fan | School of Mechanical and Electronic Control Engineering, Beijing Jiaotong University, Beijing 100044, China | | Yinlong Zuo | CRRC Tang Shan Co., LTD., Tangshan 063000, China | | Liguo Hu | CRRC Chang Chun Railway Vehicles Co., LTD., Changchun 130062, China | |
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Abstract: |
This paper presents an experimental study on the static tensile test of resistance spot welding between 2.0 mm thick dissimilar 301L-DLT and Q235B in tensile-shear specimens with different welding nugget diameters. Force-displacement curves of the specimens were compared with simulation curves by the finite element software. The stress-strain distribution and fracture evolution process during the tensile process were analyzed. The hardness of the nugget was higher than that of the base material and the heat affected zone. Under static tensile load, the stress and strain in the spot welded joints increased exponentially with the increase of displacement, and the maximum stress was located at the nugget edge of the 301L plate loading side. The static tensile strength and plastic deformation of the spot welded joint failure by the nugget pulled-out fracture mode was better than that by the interface fracture mode. The critical nugget diameter of Q235B for the transition from nugget interfacial fracture to the pull-out fracture was 7.12 mm, and that of 301L was 7.81 mm, which was about 5√t. |
Key words: 301L/Q235B dissimilar resistance spot welding static mechanical properties fracture mode finite element stress analysis |
DOI:10.11916/j.issn.1005-9113.19031 |
Clc Number:TG407 |
Fund: |
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Descriptions in Chinese: |
对301L-DLT/Q235B异种钢2.0 mm板不同熔核尺寸的电阻点焊拉剪试样进行静拉伸试验。用有限元软件模拟出了点焊接头的力-位移曲线,分析了点焊接头拉伸断裂过程的应力应变分布和断裂演变过程。熔核硬度高于板材和热影响区。在静拉伸载荷作用下,电阻点焊接头拉伸过程的应力、应变随位移增大呈指数关系增长,301L板加载侧熔核边缘的应力值最大。点焊接头以熔核拔出断裂失效试样的静拉伸强度和塑性变形量优于以界面断裂模式,由熔核界面断裂向拔出断裂转变的搭接面临界熔核直径为7.12 mm,约5√t。 |