Study Of A Single-Step Spinning Process For Disk-Like Parts With Thickened Rims

With the increasing demand for reducing energy consumption and protecting environment, it?s unfit to manufacture disk-like parts with both thin web plates and thick rims via welding and machining. This motivates new forming methods. Although sheet metal stamping-forging is an important lightweight method to make sheet metal parts, it is only applied to forming small-sized parts in the automotive and aviation industry. Therefore, a new rotary forming process for rim thickening was proposed in this paper to produce disk-like parts with both thin web plates and thick rims integrally.In the new rotary forming process, a work-piece is clamped between the upper spindle and lower spindle and all of them rotate together. A roller with outside groove feeds along the radial direction of the work-piece to thicken the rim, and rotates passively under the drive of friction between the roller and work-piece. The forming process stops when the roller contacts the upper spindle.The research on the forming process shows: it can be divided into three stages: elastic bending, roller groove filling, and flash forming. There is no plastic deformation at the first stage, and the effective plastic strain increases with the roller feeding along the radial direction. In the forming process, the radial force was greater than the tangential force, and the axial force was the smallest of all. Besides, the value of r should be less than 2.34 mm in order to avoid ?crimping?, the value of should be less than 94 in order to avoid ?premature flash?, and blank with too large size would lead to instability in the forming process.The orthogonal test results indicate: the value of, which is the ratio of maximum blank size to thickness and indexes the stability of sheet metals during forming, increases with the increasing of and r, whereas decreases with the increasing of v and. Furthermore, the influence rank of the forming parameters on the forming process and their interactions was, and the optimized parameters group under the test conditions was determined and verified.The metallographic analysis and the hardness test show: the blank anisotropy, which was caused by hot rolling, has great effects on the flow line distribution of the forming results, whereas has little effect on the hardness distribution.