Application of laser in seam welding of dissimilar steel to aluminium joints for thick structural components
Application of laser in seam welding of dissimilar steel to aluminium joints for thick structural components
复制标题
DOI：
10.1016/j.optlaseng.2014.10.006
复制
发表时间：
2015-04-01
影响因子：
4.6
通讯作者：
McPherson, N.
中科院分区：
文献类型：
--
作者：
Meco, S.;Pardal, G.;McPherson, N.
采用最大功率为8000w的连续波（CW）光纤激光器，在传导模式下将2mm厚的钢（XF350）与6mm厚的铝（AA5083-H22）以搭接方式连接在一起，钢位于顶部。钢表面被激光照射，热量通过钢板传导到钢-铝界面，铝熔化并润湿钢表面。焊接样品无缺陷，焊缝显微照片显示铁和铝原子反应形成脆性金属间化合物（IMC）层。能谱分析表明，IMC的化学计量为Fe2Al5和FeAl3， Fe2Al5的最大显微硬度为1145 HV 0.025/10。随激光加工参数的不同，IMC层厚度在4 ~ 21 pm之间变化。在恒定功率密度（PD）下，IMC层随外加比点能量（E-sp）呈指数型增长。较高的PD值加速了IMC层的生长。所有样品的机械抗剪强度变化范围窄（最大值为31.3 kN），施加的E-sp略有增加。这可以解释为，增加E-sp导致了润湿的增加，从而增加了钢-铝界面的结合面积。(C) 2014年作者。Elsevier Ltd.出版。
Laser welding-brazing technique, using a continuous wave (CW) fibre laser with 8000 W of maximum power, was applied in conduction mode to join 2 mm thick steel (XF350) to 6 mm thick aluminium (AA5083-H22), in a lap joint configuration with steel on the top. The steel surface was irradiated by the laser and the heat was conducted through the steel plate to the steel-aluminium interface, where the aluminium melts and wets the steel surface. The welded samples were defect free and the weld micrographs revealed presence of a brittle intermetallic compounds (IMC) layer resulting from reaction of Fe and Al atoms. Energy Dispersive Spectroscopy (EDS) analysis indicated the stoichiometry of the IMC as Fe2Al5 and FeAl3, the former with maximum microhardness measured of 1145 HV 0.025/10. The IMC layer thickness varied between 4 to 21 pm depending upon the laser processing parameters. The IMC layer showed an exponential growth pattern with the applied specific point energy (E-sp) at a constant power density (PD). Higher PD values accelerate the IMC layer growth. The mechanical shear strength showed a narrow band of variation in all the samples (with the maximum value registered at 31.3 kN), with a marginal increase in the applied E-sp. This could be explained by the fact that increasing the E-sp results into an increase in the wetting and thereby the bonded area in the steel-aluminium interface. (C) 2014 The Authors. Published by Elsevier Ltd.