本项目针对变形铝合金高固相分数半固态坯料难以低成本制备的技术瓶颈问题，利用锻态变形铝合金中拉长晶储存的变形能为连续加热过程中再结晶驱动力，发挥热变形本身产生的等轴晶组织优势，提出锻态变形铝合金直接半固态等温处理的制坯新方法。项目主要研究锻态变形铝合金连续加热过程中再结晶机制、锻态变形铝合金半固态等温过程球化机理、半固态坯料的流变学行为以及半固态触变成形构件的质量调控等内容。结合现有热轧板材和热挤压棒材商业大规模供货的优势，实现变形铝合金半固态坯料短流程和低成本制备。将此制坯方法应用于典型变形铝合金（2A12、5A06、7075等）通用液压机上半固态触变成形技术中，实现了低成本、短流程的半固态触变成形全过程，成形出形状复杂且力学性能高的变形铝合金结构件，为航空、航天、汽车等领域内变形铝合金结构件的成形制造提供技术支撑。

In this project, in order to solve the bottleneck problem of low-cost-fabrication of wrought aluminum semisolid billet with high solid fraction, a novel method called direct semisolid isothermal treatment of wrought aluminum alloy (DSSITWAA) is firstly proposed. In this novel method, deformation storage energy created in elongated grains is used as a recrystallization driving force during the continuous heating course.In addition, equiaxed grains created in hot deformation process also exhibit a microstructure advantage in this novel method. The main research contents include recrystallization mechanism of wrought aluminum alloy during continuous heating, spheroidization mechanism of wrought aluminum alloy during semisolid isothermal treatment, rheological behavior of semisolid billet and quality control of thixoformed products. Low-cost and short-process fabrication of semisolid billet is realized by combining the advantage of commercial mass supply of hot-rolled plates and hot-extruded bars. Low-cost and short-process thixoforming process is also achieved by applying DSSITWAA method to thixoforming process of typical wrought aluminum alloys such as 2A12, 5A06 and 7075 via a general hydraulic press machine. In addition, complex structure components of wrought aluminum alloy with high mechanical properties are thixoformed successfully. It will provide a technology support to forming structure components of wrought aluminum alloy in the fields of aviation, aerospace and automotive.