镁合金带内筋筒形件热强旋成形及性能调控基础研究

Aiming at the increasing demand of requirements for lightweight, high precision and high property structure in the aerospace, missile weapons and transportation fields, the research of the fundamental theory and technology on hot power spinning forming and property control of magnesium alloy cylindrical parts with inner ribs is proposed. Focusing on the scientific issues such as texture evolution and recrystallization nucleation mechanisms of hot power spinning forming and material flowing behavior of cylindrical parts with inner ribs during hot power spinning forming under the condition of thermo-mechanical coupled, the study of the hot power spinning formability, thermoplastic deformation mechanism, heating and temperature control methods, hot power spinning forming and property control mechanism of magnesium alloy is put forward, and the thermo-mechanical coupling finite element model of texture evolution and deformation-heat transmission-microstructure evolution is established to realize the multi-scale coupling simulation of macroscopic plastic deformation and microstructure evolution during hot power spinning and to reveal the essence of this deformation process; The corresponding spinning equipment will be developed and the relevant theory will be verified by experiments, the precision/property integrated control method of macroscopic dimension precision and microstructure property of magnesium alloy cylindrical parts with inner ribs will be attained. It will provide theoretical basis and technical reserve for the preparation of key components in the fields of aerospace and transportation, and has important scientific significance and remarkable practical value for the development and improvement of magnesium alloy thermoplastic forming theory and hot power spinning technology.

针对航空航天、武器导弹及交通运输领域对结构轻量化、高精度、高性能要求日益提升的需求，提出对带内筋镁合金筒形件热强旋成形及性能调控基础理论与技术进行研究。围绕镁合金热强旋成形时织构演变及再结晶形核机制和热力耦合条件下热强旋成形带内筋筒形件时的材料流变特性等科学问题，提出对镁合金热强旋成形性能、热塑性变形机制、加热及温度控制方法、热强旋成形及性能调控机理等进行研究，构建出镁合金热强旋织构演变及变形-传热-微观组织演变热力耦合有限元模型，以实现热强旋过程宏观塑性变形和微观组织演变的多尺度耦合模拟，揭示其塑性变形的本质；研制出相应的工艺装备并对相关理论进行实验验证，获得镁合金带内筋筒形件宏观尺寸精度及微观组织性能形/性一体化控制的方法，为我国航空航天和交通运输等领域关键零部件的制备提供理论基础及技术储备，对镁合金热塑性成形理论和热强旋技术的发展和完善都具有重要科学意义和显著的实用价值。

航空航天、武器导弹及交通运输领域高端装备迫切需要大量采用兼具高精度与高性能的镁合金带内筋筒形件，以减轻装备重量和提高整体性能。项目采用热强旋方法实现了ZK61高强镁合金带内筋筒形件的少无切削近净成形，并对其热强旋成形机理及性能调控基础理论与技术展开了深入研究。提出采用单向热压缩试验作为带内筋筒形件热强旋反旋时的物理模拟试验，构建了可准确描述ZK61镁合金热塑性变形行为的高温本构模型。建立了镁合金三维热加工图及激活能图，实现了对ZK61镁合金热加工窗口的精确表征。建立了镁合金管坯电磁感应加热模型，实现了对热强旋旋前管坯温度场分布的预测。建立了耦合三维热加工图的热强旋变形-传热有限元模型，揭示了镁合金带内筋筒形件热强旋成形机理，获得了有利于镁合金热强旋变形及微观组织演变的工艺条件。建立了镁合金带内筋筒形件热强旋微观组织演变元胞自动机模型及织构演变晶体塑性有限元模型，解决了多尺度耦合模型边界条件等建模关键技术问题，实现了热强旋过程微观组织及织构演变的可视化预测。研制出了热强旋成形工艺装备，实现了对旋转中的毛坯温度非接触式精确测量，并进行了ZK61镁合金带内筋筒形件热强旋成形试验研究。分析了热强旋过程镁合金带内筋筒形件存在的成形缺陷，提出了旋压件内筋充填质量的评价指标，获得了旋压工艺参数对旋压件成形质量的影响规律。采用正交试验与灰色关联度法，获得了成形参数对旋压件成形质量指标影响的主次顺序以及优化的参数组合。基于所获得有利于热强旋过程形/性一体化控制的工艺条件，制备出了质量合格且微观组织均匀的镁合金带内筋筒形件。采用热强旋方法制备的镁合金带内筋筒形件，屈服强度和抗拉强度与坯料基本相同，壁部和筋部的延伸率分别提高了52.2%和39.8%。本项目的完成，实现了镁合金带内筋筒形件的低成本高性能精确成形制造，对推动航空航天等领域高端装备成形成性一体化制备技术的发展和完善，均具有重要的科学意义和应用价值。