管料无芯轴凹进式旋转锻造变形规律研究

Research of deforming law during non-mandrel recessed rotary forging process for tube

无芯轴凹进式旋转锻造是一种用于管料精密制造的渐进近净成形工艺,广泛应用于航空航天、汽车制造等领域。本文基于有限元软件TRANSVALOR FORGE 2011,建立了管料无芯轴凹进式旋转锻造成形三维有限元模型,研究了成形过程中的应力状态和残余应力状态。结果表明,工件不同区域材料应力状态不同,工件外壁材料受三向压应力,应力变化较为剧烈;工件中间层材料受环向和径向两向压应力,而轴向应力趋于零;工件内壁材料受轴向拉应力,环向和径向压应力。卸载后,材料内部仍然存在保持自相平衡的三向残余应力,最大值为57.2MPa,仅为材料屈服应力的63.6%。凹进式旋转锻造成形过程中所产生的变形,满足应力偏张量的第三不变量J3′<0,属于压缩类变形。

On the basis of TRANSVALOR FORGE 2011finite element （FE） simulation software, the 3D FE model has been established to the non-mandrel recessed rotary forging process for tube in order to study the state of stress and the residual stress. The results show that the stress state varies with the regions. The outer wall material of the work piece suffers from three-way stress, which fluctuatessharply. The middle ma- terialbears circumferential and radial stress while the axial stress tends to be zero. The inner wall material stands axial, circumferential, and radial stress. After being unloaded, the residual stress that can keep bal- ance has been existed in inner of material. The maximum residual stress is 57.2MPa, which is only 63.6% of the yield stress. The deformation during non-mandrel recessed rotary forging process can satisfy the law that the third invariant of stress deviation J3＇is less than 0, which belongs to compression deformation.