Research On Residual Stress Reduction Process Of GH4169 Alloy Ring

GH4169 alloy ring has large residual stress,which will increase the production cost,reduce the fatigue strength and affect the improvement of the overall performance of the ring.In order to reduce the residual stress of GH4169 alloy ring,a finite element model of GH4169 alloy ring radial-axial rolling was established to explore the influence of the core roller feed speed,driving roll speed,ring blank temperature,driving roller radius,core roller radius on the residual stress of the ring,and the process parameters that produce less residual stress are explored.In addition,the plastic deformation method is also studied to reduce the residual stress of GH4169 alloy.In addition,the residual stress reduction of GH4169 Alloy by plastic deformation was studied.The residual stress and dislocation distribution of GH4169 alloy before and after plastic deformation were analyzed by X-ray residual stress tester,X-ray diffraction(XRD)and electron backscatter diffraction(EBSD)and the effect and micro mechanism of plastic deformation method to reduce residual stress of GH4169 alloy were studied.It provides a method and theoretical guidance for GH4169 alloy ring to reduce residual stress by plastic deformation.The results show that:(1)The rolling process parameters have an important influence on the residual stress of the GH4169 alloy ring.With the increase of the core roller feed speed,the hoop residual stress increases,but the radial residual stress does not change significantly.With the increase of driving roller speed,the radial residual stress decreases,and the hoop residual stress first decreases and then increases.With the increase of the ring temperature,the radial and hoop residual stresses increase.With the increase of the driving roller radius,the radial and hoop residual stresses decrease.With the increase of the core roller radius,the hoop residual stress first increases and then decreases,but the radial residual stress is not affected.(2)The better values of the ring rolling process parameters that produce less residual stress are obtained.When the core roller feed speed is 0.8 mm/s,the driving roller speed is 5.0 rad/s,the ring blank temperature is 900 ?,the driving roller radius is 270 mm,and the core roller radius is 86 mm,the residual stress in the GH4169 alloy ring is relatively small.(3)The plastic deformation method can effectively reduce the residual stress of GH4169 alloy.The tensile plastic deformation can effectively reduce the residual compressive stress in the GH4169 alloy.When the tensile plastic deformation is 3%,the reduction rate of the residual compressive stress reaches the maximum value of 91%.Compression plastic deformation can effectively reduce the residual tensile stress in the GH4169 alloy.When the compression plastic deformation is 3%,the reduction rate of the residual tensile stress reaches the maximum value,which is 93%.(4)Revealing the microscopic mechanism of the plastic deformation method to reduce the residual stress of GH4169 alloy.After plastic deformation,the dislocation distribution in the GH4169 alloy is more uniform,which is the reason for the relaxation of the residual stress.