扭曲面作为一种典型三维曲面件, 有着广泛的应用, 但由于形状复杂, 成形困难。激光热成形利用热累积成形, 加工中不直接接触板件, 具有很好的加工柔性, 是三维曲面件成形的重要工艺途径。阐述了扭曲面激光热成形工艺内容, 通过曲面展开算法, 获取展开曲面形状; 利用特征应变, 形成激光加热路径在展开曲面上的分布; 结合工艺数据库, 完成各激光加热路径上的加工参数确定。基于激光加工实验平台, 对扭曲面进行了实验加工, 结合形貌测量, 扭曲面的形状均方误差为421.2 μm, 验证了提出的曲面展开、加工路径和工艺参数规划方法的有效性, 为复杂曲面成形提供了技术方法。

The twisted surface is a typical three-dimensional curved plate and is widely applied, while it is hard to be formed due to complicated shape. As a non-touch forming method of hot accumulation, laser forming is flexible and suitable for the forming of curved plate, is an important three-dimensional curved plate forming process. Oriented to process planning of laser forming for twisted surface, the shape of developed plate, layout of laser heating paths and heating parameters of every path are calculated and planned by surface development algorithm, characteristic strain field and database of process parameters respectively. Furthermore, the experimental verification and shape error analysis are carried out on experimental platform of laser forming. The mean square error of shape is 421.2 μm, which proves the validity of the proposed method for surface expansion, processing path and process parameter planning, provides a technical method for complex curved surface forming.