Abstract:The material undergoes the complex uneven plastic deformation and microstructure evolution process coupled with multi-fields and multi-factor, during the multi-path roll forming process of the thin-walled super alloy (GH4169) ring with complex section. Especially for the uneven plastic deformation which usually leads to defects of the ring, such as wrinkling, ellipse and crack. Friction is the main parameter to describe the contact between ring and roller, which largely determines the inhomogeneity of plastic deformation during the multi-path rolling process of the thin-walled high temperature alloy (GH4169) ring with w section. And it seriously affects the improvement of roll forming quality. To predict and control the nonuniform plastic deformation, a 3D FE model of the process was built under the ABAQUS/Explicit environment. And the representation method of the nonuniform deformation is proposed.Then the nonuniform deformation behavior in the process was analyzed systematically using FE method combined with experiment and theory. The results show that the maximum value of the equivalent stress increases gradually with the progress of the multi-pass rolling process. And the deformation degree slightly decreases firstly, and then increases gradually with the increase of the friction coefficients between the thin-walled ring and slave roller, drive roller. While the effection of the friction coefficient between guide roller and the ring on the deformation degree can be neglected.