Optimization of the Forging Process Parameters of the FGH4113A P/M superalloy turbine disk based on response surface method

Abstract:

In this work, the macro-micro coupled finite element simulation of the FGH4113A P/M superalloy during the forging process was carried out and systematically studied. The effects of workpiece temperature, die temperature, height-diameter-ratio of the workpiece, and strain rate on the microscopic average grain size (d_ave) and its distribution uniformity of the forged turbine disks were analyzed by single factor simulation. Based on the orthogonal experimental design and response surface method, the mapping relationship between processing parameters and microstructure state variables was established. The d_ave and the standard deviation of grain size distribution were taken as the optimization targets of processing parameters to achieve microstructural control. Then the optimal processing parameters can be obtained by multi-objective optimization of the established response surface model, listed as: the workpiece temperature of 1097℃, the die temperature of 976℃, height-diameter-ratio of 2.4, and strain rate of 0.021s^_-1. The validated finite simulation under this deformation condition was carried out to verify the reliability of the optimization results. The results show that the forged turbine disk depicts the characteristics of the finer d_ave and uniform grain size distribution. This study can provide the guidelines and reference for process formulation in the production process of high-performance superalloy turbine disks.

Key words:Response surface method; Superalloy; turbine disk; Optimization of processing parameters