网格式整体壁板增量成形有限元模拟

将机加后的平面外形的壁板毛坯成形为具有复杂曲面外形的壁板零件具有很大难度,为此,采用有限元方法进行壁板成形工艺模拟,分析壁板加工过程中的应力应变分布与失稳开裂现象.研究表明:网格式整体壁板增量成形过程中,塑性变形主要集中于筋条处,成形后的壁板主要是由于筋条发生塑性变形而导致壁板外形的改变.在成形过程中,筋条容易出现失稳与开裂现象.采用分段逐点循环模拟的方法,实现了网格式整体壁板结构件增量成形过程的数值模拟.

Simulation of incremental formingon integral panel skin with grid-type ribs

Integral wing-skin panel with grid-type ribs is a kind of light-weight structure, which applied in the aerospace field widely. The characteristic of this structure is that the skin and the grid-type ribs are a whole body. It is very difficult to form the machined panel into required shape. FEM is used to study the incremental forming technology. The research indicates that the buckling or the fracture may occur on the ribs in the processing. In the process of incremental press bending, the skin is in elastic state while the ribs have not only elastic deformation but also plastic deformation. The outline change of the workpieces will mainly be determined by the deformation of the ribs. The method of the point-to-point module of cycles is proposed, which effectively solved the problem of the incremental forming in the integral panel skin.