基于响应面法的大型铝合金锻件的多目标成形优化

Multi-objective optimization of forming process for large-scale Al alloy forging based on RSM

以大型铝合金锻件为研究对象,以锻件的应变均匀性及锻造变形力作为评价指标,提出了采用正交实验并进行响应面法建模分析,得到了二阶响应面模型。通过数值模拟验证模型准确性,可用于后续优化。求得目标函数设计空间中的最佳工艺参数组合为:飞边槽高度3.56 mm、锻造温度451℃、摩擦系数0.35和成形速率7.25 mm·s-1。采用Deform对优化后的工艺参数进行验证,优化后锻件的成形均匀性较好,并可以降低锻件成形载荷。根据优化结果,对铝合金锻件进行生产试制,结果表明,通过多目标优化后得到的锻件尺寸及性能均满足要求,设备成形载荷能较好地满足要求。

Large-scale aluminum alloy forging being regarded as the object of study and using the strain uniformity and forging force of forging as the evaluation index, the orthogonal experiment and modelling analysis of response surface method were put forward and carried out, respectively, and the second order response surface model was obtained. The accurate model was verified by numerical simulation for the following optimization. The optimum parameters that flash tank height of 3.56 mm, forming temperature of 451 ℃, friction coefficient of 0. 35 and forming speed of 10 mm s-1 in feasible design space are obtained. The optimized process parameters were verified by Deform. The forming uniformity of forging is good after optimization, and the forging force is reduced effectively. The production practice of Al alloy forging was done based on the optimized results, which shows that the size and property of forging after multi-objective optimiza- tion are satisfied, and so does the forming force of equipment.