铸钢基体双金属梯度制备锻模焊层厚度研究

Research on Preparation of Welding Layer Thickness of Forging Die with Dual Metal Gradient on Casting-steel Matrix

将试验与有限元数值分析相结合,建立了某飞机起落架模具模型。采用弹塑性有限元方法模拟了坯料锻造成形过程,并分析了不同时刻模具温度场和应力场。结果表明,随时间增加,模具应力及温度均上升,模具充满时达到最大值,等效应力最大值出现在模具桥部圆角处,并且应力与温度随与该位置距离的增加而减小。分析坯料填充饱满时参考线位置的状态,结合实验得到铸钢基体、过渡层、表面层材料随温度变化的压缩屈服强度曲线,综合考虑各焊层厚度对模具性能的影响及控制模具制造成本等因素,设计在该工况条件下铸钢基体双金属梯度层总厚度为16 mm,其中表面强化层和过渡层的最优厚度均为8 mm。

Combined test with finite element numerical analysis, the model of the aircraft landing gear die was established. The forging forming process of blank was simulated by using elastic-plastic FE method. And temperature field and stress field of the die at different times were analyzed. The results show that, with the increase of the time, the die stress and temperature rise, which reaches a maximum when the die is full, and the maximum equivalent stress is at the rounded comers of the die bridge, and the stress and the temperature decreases with the increase of the distance of the location. Analyzing the working status of the reference line position while blank is full, combined with compression yield strength curves of cast steel substrate, transition layer and surface layer material along with the temperature changing, overall considering the effect of weld thickness on the properties of the die and the cost of the die manufacturing, the design of total thickness of cast steel matrix double metal gradient layer is 16 mm under the working conditions. And the optimum thickness of surface strengthening layer and transition layer is 8 mm separately.