大型薄壁异型曲面旋压不均匀变形机理与精确成形调控

How to manufacture large thin-walled complex surface components without welding is an urgent demand of advanced aerospace equipments. Research on it has become one of important and challengeable issues in the international frontier of plastic processing field. Thus, this project proposed a method to preform wide blanks by spinning then spin the blanks into the large thin-walled complex surface components. Therefore it is urgent to research and resolve the inhomogeneous deformation mechanism of large thin-walled complex surface components during spinning and how to precision control its deformation, which is a key scientific and technical issue. This project will establish an FE model for the whole process including multi-pass spinning and springback of large thin-walled complicated components, considering material and geometric properties and deformation history, coupled with damage, and a thermo mechanical coupled finite element model for quenching deformation considering the forming history of large thin-walled complex surface spun parts, and including heating, thermal insulation and cooling stages. Reveal defects’ mechanism and its relationship with the non-uniform deformation, and the key parameters and their influence on the spinning and quenching of large thin-walled complex surface components. Establish the relationship among quenching residual stress, quenching deformation and spinning residual stress, and propose a quality control method for optimizing the whole spinning and quenching process, finally realize the comprehensive regulation of the quality of a typical large thin-walled complicated component with curved surface. The research results are significant to the development of advanced theory and technology of integrated manufacturing without welding of large thin-walled complex surface components.

如何实现大型薄壁异型曲面复杂构件无焊缝整体制造是航天高端装备发展重大而迫切的需求，其研究已成为国际塑性加工学科前沿领域重要和挑战性课题。为此，本项目提出通过旋压预制整体超宽板坯，然后再旋压成形大型薄壁异型曲面的技术路线和方法，而大型薄壁异型曲面旋压不均匀变形机理与精确成形调控是其中迫切需要研究解决的关键科学技术问题。因此，本项目研究引入预制坯材料特性和构件变形历史，并耦合损伤，建立大型薄壁异型曲面多道次旋压、回弹全过程有限元仿真模型，以及加热、保温和冷却全过程淬火变形热力耦合有限元模型；揭示不均匀变形与成形缺陷形成机理及其关系，关键参数对大型薄壁异型曲面旋压成形和淬火变形的影响规律；建立淬火变形与残余应力和旋压残余应力的关联模型；研究提出典型大型薄壁异型曲面构件精确成形全过程质量综合调控(旋压与淬火)方法。其结果对提高大型薄壁异型曲面复杂构件无焊缝整体制造能力和制造技术水平具有重要意义。

本项目针对大型薄壁异型曲面构件旋压成形仿真模型缺失，成形机理与规律不明、易破裂、起皱、淬火变形制约精确成形且难调控等科学与技术难题，采用理论分析、数值模拟仿真和缩比件实验与1:1样件试制相结合的方法，对其旋压与淬火全过程开展了系统研究。分析了2219铝合金的变形与损伤行为，建立了耦合材料各向异性和损伤及包申格效应的旋压变形本构模型；研究了材料在宽温度范围的变形行为，建立了淬火加热和冷却全过程的本构模型。研究了坯料的几何波动特征，建立了大型薄壁异型曲面构件旋压-回弹全过程有限元模型和淬火加热-冷却变形有限元模型。分析了大型薄壁异型曲面构件旋压的不均匀变形特征与缺陷形成机理，建立了预测模型与控制方法。研究了坯料和工艺条件对旋压成形的影响与关联关系，据此优化了旋压工艺。研究了大型薄壁异型曲面旋压件和薄板的淬火变形行为和工艺参数的影响规律，提出了旋压-淬火联合的变形综合调控方法。以直径3.35m的燃料贮箱箱底封头为典型应用对象，设计制造了旋压工模具，搭建了缩比模型试验平台和大型薄壁异型曲面件旋压平台，成功旋制了缩比件和型面误差不超过3mm的1:1样件。研究提升了我国航天领域的大型薄壁复杂构件整体成形制造的能力与水平，为未来更大运载能力和更远射程导弹用大型薄壁复杂构件的整体成形制造提供了借鉴。对现役和未来火箭和导弹的运载能力、覆盖范围、可靠性，以及我国的战略储备和威慑能力提升具有重要价值和意义。