薄壁弧形件装夹布局有限元优化

关于航空结构件加工变形控制的研究是高效数控加工研究的一部分。薄壁弧形零件加工中的弹性变形对加工质量影响很大,而装夹布局影响切削变形的大小和分布。以减少加工中工件最大弹性变形为目标,建立了弧形件铣削加工装夹布局的优化模型,采用商业有限元软件的设计优化模块进行计算。在对计算结果进一步分析的基础上,提出了最终的装夹布局方案,采用该方案可以得到整个加工过程中更低的变形量,变形分布更均匀,为采取相应数控补偿措施提供条件。优化方案和实际加工方案结果基本一致。所提出方法可推广至其他类型工件夹具布局优化设计。

FINITE ELEMENT OPTIMIZATION OF MACHINING FIXTURE LAYOUT OF THIN-WALLED ARC WORKPIECE

Deformations of aerospace structure parts during NC machining decrease accuracy. Thin-walled arc workpieces suffer more seriously as there are more uncertainty and comp- lexity in their machining and alignment. Fixture layout can influence the workpiece machining deformation by changing the rigidity of fixture-workpiece system. A model for reducing elastic deformation in machining through optimal placement of fixture clamps around the workpiece, is presented. The layout optimization model which is developed and carried out by FEM is shown to improve the overall workpiece deformation and distribution condition.