高强铝合金分区温控热冲压梯度温度场精确成形机理研究

In high-strength aluminum hot stamping process, the plastic deformation is usually concentrated in the high temperature zone due to the interfacial heat transfer between the sheet and the dies, which causes this zone to be easily thinned or even cracked. This phenomenon seriously reduces the forming quality of hot-stamped high-strength aluminum parts in complex shape, and it seriously restricts the process’s further application in automotive industry. To solve this problem, this project proposes a partition temperature control technology to improve the forming quality of the aluminum parts by reasonably controlling the temperature gradient distribution of the sheet during the hot stamping process. In this project, partition temperature control will be achieved by utilizing a heat-conducting plate and variable temperature distribution dies. Thermophysical simulation experiments, microstructure observations, and unified viscoplastic model construction will be used to reveal the thermoplastic deformation mechanism and gradient distribution mechanism of microstructure and mechanical property in gradient temperature field. The feasibility of the partition temperature control technology will be verified by finite element technology and anti-collision beam hot stamping experiment. The thickness, microstructure, and mechanical property distribution in specific zone of the specimen will be accurately predicted and controlled. Finally, the high-strength aluminum parts in complex shape will be precisely hot stamped. This project provides a scientific basis for rationally controlling the forming quality in specific zone of the parts, which helps to improve the manufacturing process level of China's automobile industry.

高强铝合金板材在热冲压过程中，由于板料与模具之间界面换热的影响，塑性变形通常集中于板料高温区，导致该区域易产生明显减薄甚至开裂。该现象严重降低了高强铝合金复杂形状零件的热冲压成形质量，是限制该工艺在汽车领域进一步发展应用的关键问题。针对这一问题，本项目提出高强铝合金分区温控热冲压技术，通过合理控制板料在成形过程中的温度梯度分布，以提升板料在易减薄区域的成形质量。项目拟采用合理设计导热板结构、改变模具温度等技术手段实现分区温控；通过热物理模拟实验、微观组织观察、统一本构建模等方法，揭示梯度温度场下高强铝合金的热塑性变形机理与组织性能梯度分布机理；借助有限元技术和防撞梁热冲压实验，验证分区温控技术的可行性，精确预测和控制试样局部区域的厚度与组织性能分布，最终实现高强铝合金复杂形状零件的热冲压精确成形。该项目可为合理调控成形件局部区域成形质量提供科学依据，有助于提升我国汽车工业的制造工艺水平。

本项目提出高强铝合金分区温控热冲压技术，通过合理控制板料在成形过程中的温度梯度分布，以提升板料在易减薄区域的成形质量。项目采用合理设计导热板结构、改变模具温度等技术手段实现分区温控；通过热物理模拟实验、微观组织观察、统一本构建模等方法，揭示梯度温度场下高强铝合金的热塑性变形机理；借助有限元技术和人工智能算法，精确预测和控制试样局部区域的成形质量分布，最终实现高强铝合金复杂形状零件的热冲压精确成形。该项目可为合理调控成形件局部区域成形质量提供科学依据，有助于提升我国汽车工业的制造工艺水平。在项目资助下，发表9篇SCI学术论文（均为第一标注），授权发明专利2项。