Accuracy control of hot bending for Inconel 718 superalloy thick plate

Based on an Inconel 718 superalloy thick plate bending product with gradient radius (thickness: 12 mm), the accuracy control of hot bending was studied by the finite element method numerical simulation and experimental test. Meanwhile, the effects of bending die gap and friction coefficients were investigated using Deform‐3D, and the parameters of the hot bending test have been improved. The results show that radial deviations decrease with reduction in the gap between male and female dies as the friction coefficients are fixed, and decrease as the friction coefficients rise when the die gap settles. In addition, radial deviations of the area, which are close to the plate’s border, rise with the decrease in distance to the border. According to the results, an Inconel 718 thick plate bending product with gradient radius has been formed on a hydraulic machine of 5000 kN with improved parameters. The radial accuracy of thick bending plate meets the requirements (R±0·5 mm).