基于Kriging模型的超高强度钢板热冲压工艺参数优化

为了改善超高强度钢板冲压件的加工质量,以某方形槽热冲压件为对象,以板料淬火温度、模具初始温度、冲压速度和模具间隙为设计变量,以冲压件成形温降、回弹量和成形减薄率3个质量指标为响应量,构建了热冲压加工质量指标的Kriging模型。在此基础上,以构建的Kriging模型为目标函数,建立超高强度钢板热冲压工艺参数多目标优化模型。应用第二代非支配遗传算法进行寻优计算,获得了优化的热冲压工艺参数:B1500HS超高强度钢板零件热冲压的最佳淬火温度为898.3℃,模具的初始温度为67.1℃,冲压速度为39.64 mm·s-1,模具间隙为2.2 mm。工艺参数优化后的验算结果表明,工艺参数优化后,成形温度更加均匀,回弹量减少25.6%,最大减薄率下降23%。

Optimization on hot stamping process parameters of ultra high strength steel based on Kriging model

To improve the processing quality of hot stamping for ultra high strength steel,taking a square slot as an example,the processing quality index Kriging model was constructed with the design variables of hardening temperature,die initial temperature,stamping velocity,die clearance and the responses values of temperature drop,springhack value and thickness reduction ratio.On this basis,a multi -objective optimization model of process parameters was established with objective function of the constructed Kfiging model.Then,the optimal process parameters of hot stamping were searched by non-dominated sorting genetic algorithm Ⅱ.The concrete optimal process parameters of B1500HS ultra high strength steel were obtained at quenching temperature of 898.3 ℃,die initial temperature of 67.1 ℃,stamping velocity of 39.64 mm · s-1 and die clearance of 2.2 mm.The checking results after optimization indicate that the forming temperature is more uniform,the springback amount declines by 25.6％,and the thinning ratio reduces by 23％.