Small strain finite element modelling of friction stir spot welding of Al and Mg alloys
Small strain finite element modelling of friction stir spot welding of Al and Mg alloys
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DOI：
10.1016/j.jmatprotec.2018.07.031
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发表时间：
2019-01-01
影响因子：
6.3
通讯作者：
Shercliff, H. R.
中科院分区：
文献类型：
--
作者：
Jedrasiak, P.;Shercliff, H. R.
建立了铝、镁合金搅拌摩擦焊接过程中发热量和温度随时间和空间变化的有限元模型。加热摩擦和体积塑性计算间隔使用小应变弹塑性分析的一个工具旋转的一小部分。这与在整个焊接循环中运行的常规热分析并行运行。该模型进行了测试，在两个工具的旋转速度与实验数据的三个变形铝合金，和两个铸造合金（一个铝和一个镁）。热生成的历史被发现是非常相似的转速和所有五种合金。该模型的一个关键方面是在工具-工件界面处使用基于物理的运动学边界条件，其中表面速度分布具有内部粘附区域和外部滑动区域。该方法显示了快速计算的热输入和温度场在大应变摩擦过程，如FSSW，而不依赖于完全耦合显式有限元分析的潜力。
A finite element model was developed to predict the spatial and temporal variation of heat generation and temperature in FSSW of aluminium and magnesium alloys. Heating by friction and bulk plasticity is computed at intervals using small-strain elastic-plastic analysis for a small fraction of one tool rotation. This runs in parallel with a conventional thermal analysis running for the whole weld cycle. The model was tested at two tool rotation speeds with experimental data for three wrought aluminium alloys, and two casting alloys (one aluminium and one magnesium). Heat generation history was found to be remarkably similar for both rotation speeds and across all five alloys. A key aspect of the model is the use of a physically-based kinematic boundary condition at the tool-workpiece interface, with the surface velocity profile having an inner sticking region and an outer slipping region. The method shows the potential for rapid calculation of heat input and temperature fields in large strain frictional processes such as FSSW, without recourse to fully coupled explicit FE analysis.