研究了蛇形轧制工艺参数对铝合金厚板变形与残余应力分布的影响.基于蛇形轧制的咬入条件与本构模型以及边界条件等关键技术,构建了铝合金厚板的单道次蛇形轧制有限元模型,并与相关文献的仿真结果进行了比较, 结果显示其相对误差不超过10%.考虑最小、最大压下量均相等的条件下压下量分配对蛇形轧制的影响,建立了多道次蛇形轧制的有限元模型并进行了仿真实验.结果表明:铝厚板应变不是按板厚中心面呈对称分布,慢速辊一侧的应变明显小于快速辊一侧, 而且压下量对称递增分配产生的应变最大,单向递增分配产生的应变最小,对称递增比单向递增分配压下量产生的应变平均要高出20%左右.此外,压下量对称递减分配引起的剪切应变最大,单向递增分配引起的剪切应变最小,对称递减分配比单向递增分配压下量产生的剪切应变要高出2倍.%The effects of process parameters in a snake hot rolling on the deformation and residual stress distribution of an aluminum alloy thick plate were explored.On the basis of the bite conditions of snake rolling, constitutive model, boundary conditions and other critical technologies, a finite element model of single-pass snake rolling for the aluminum alloy thick plate was established.The simulation results were compared with that of corresponding literatures, and it shows that the relative error is no more than 10%.In condition of the influence of pass reduction distribution on snake rolling at both minimum and maximum pass reductions being equal, the finite element model of multi-pass snake hot rolling was established and a simulation experiment was performed.The result shows that the equivalent strain of aluminum thick plate is not symmetrically distributed in accordance with the central surface;the equivalent strain near the slow roller is obviously smaller than that near the high-speed roller.Moreover, the maximum equivalent strain is generated from the symmetrical increasing distribution of pass reduction and the minimum equivalent strain is generated from one-way increasing distribution.The equivalent strain generated from symmetrical increasing distribution of pass reduction is averagely 20% larger than that generated from one-way increasing distribution.Furthermore, the shear strain generated from symmetrical decreasing distribution is twice that from one-way decreasing distribution,in which the former is the maximum and the latter is the minimum.
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