高强高韧铝合金超厚板蛇形轧制的变形特性研究

The thick plate of aluminum alloy with high strength and toughness is very important structural material, widely used in industry of aerospace, aviation and vehicle. Hot rolling is the most key procedure to manufacture the thick plate of aluminum alloy. However, limited by roll gap of rolling mill and ingot thickness, symmetrical rolling couldn't make the thick plate deformed sufficiently. As a result, the deformation, microstructure and performance of the plate between surface and center will be nonuniform. Snake rolling can increase deformation of plate without increasing reduction, this is helpful to increase the deformation in plate center, meanwhile improve the homogeneity of deformation, microstructure and performance of the plate. This paper analyzes deformation behavior on snake rolling of extra-thick plate of aluminum alloy with high strength and toughness using theoretical analysis，experimental research and numerical simulation. This project analyzes deformation behavior on snake rolling of extra-thick plate of aluminum alloy with high strength and toughness using theoretical analysis，experimental research and numerical simulation. The finite element model for snake rolling of aluminum alloy is studied, which includes models of heat transfer, deformation and microstructural evolution. By using numerical simulation technology, the influences of rolling parameters on deformation and microstructure properties of extra-thick plate in snake rolling are studied. Realize the accurate control of temperature, deformation and microstructure in snake rolling. This is helpful to increase the deformation in plate center, meanwhile improve the homogeneity of deformation, microstructure and performance of the plate. This research has offered the solid theory foundation for developed with independent intellectual property rights on snake rolling of extra-thick plate of aluminum alloy. So, the study on deformation behavior of snake rolling of the extra-thick plate of aluminum alloy is very helpful for improving the development of aluminum industry of China.

高强高韧铝合金厚板是现代航空航天、船舶制造及交通运输等领域中极为重要的结构材料。热轧是制备高强高韧铝合金厚板工艺中最关键的变形手段，但由于受现有轧机开口度及坯料原始厚度的限制，造成同步轧制生产的超大厚度板材芯部变形不充分，组织、性能不均一。蛇形轧制可在不增加压下量的前提下，增加厚板的芯部变形，改善超厚板组织的均匀性。本项目拟采用理论分析、数值模拟和实验研究相结合的方法，揭示高强高韧铝合金超厚板蛇形轧制过程中的变形特性；建立变形、传热和组织多场耦合的数值模拟系统；通过数值模拟研究蛇形轧制工艺参数对铝合金超厚板变形及组织性能的影响规律；实现蛇形轧制过程中温度、变形及组织的精确控制，最终获得芯部变形充分、板形良好的超大厚度板材。为建立适用性更强、具有自主知识产权的铝合金超厚板轧制技术提供坚实的理论支撑。研究成果有助于提高我国的厚板制造技术，对我国铝加工业的发展具有十分重要的意义。

高强高韧铝合金厚板是现代航空航天、船舶制造及交通运输等领域中极为重要的结构材料。热轧是制备高强高韧铝合金厚板工艺中最关键的变形手段，但由于受现有轧机开口度及坯料原始厚度的限制，造成同步轧制生产的超大厚度板材芯部变形不充分，组织、性能不均一。蛇形轧制可在不增加压下量的前提下，增加厚板的芯部变形，改善超厚板组织的均匀性。本项目建立了变形、传热和组织多场耦合的蛇形轧制过程的数值模拟系统；通过数值模拟研究了铝合金超厚板蛇形轧制中金属的流动变形特性，竖直和水平方向轧辊的受力以及轧制参数对轧板曲率的影响；研究了多道次蛇形轧制中，不同道次压下量、异速比对轧板温度、轧辊受力、等效应变及再结晶百分比的影响，最终获得芯部变形充分、板形良好的超大厚度板材。为建立适用性更强、具有自主知识产权的铝合金超厚板轧制技术提供坚实的理论支撑。研究成果有助于提高我国的厚板制造技术，对我国铝加工业的发展具有十分重要的意义。