超高强钢热成形损伤控制与引导车身抗撞零件性能优化设计研究

This research aims to reduce the weight and also meet the safety requirements for passenger cars. A new integrated design methodology has been proposed in this proposal, which enables the damage created in hot stamping of components to be carried for component design, so that the damage of UHSS( Ultra High Strength Steel） impact beams could be predicted and controlled in both hot stamping and in service conditions and the failure of impact components could be induced. A new testing method will be developed for obtaining FLD for hot stamping of UHSS, so that the formability of the materials could be assessed. Continuum damage mechanics based unified viscoplastic constitutive equations will be established for the prediction of the formability and failure of UHSS in hot stamping conditions, The damage in hot stamping will be carried in component design and the damage integration between hot stamping d and high speed impact will be characterised and rationalised, so that a new concept and modelling framework with the interaction of two different damage mechanisms will be created for precision impact simulation with the consideration of the damage histories in hot stamping. Based on the research on the prediction of damage evolution in hot stamping, damage levels and distribution of formed parts could be controlled and induced, so that the impact resistance of safety critical components could be altered. This would achieve the ideal energy absorption and deformation behaviour, thus to increase the capability of impact resistance. This research project will effectively integrate component impact resistance design optimization with hot stamping damage optimization together, thus the design could be achieved according to property requirements and manufacturing conditions, so that lightweight could be maximized with the secured optimal impact resistant behavior. This will be a research trend and hot research topic in the future for lightweight and safe design vehicles.

本研究是以汽车轻量化和安全性为目的，对超高强钢车身碰撞零件热成形损伤进行预测和控制，提出一种基于损伤控制和诱导的零件碰撞性能与成形一体化设计的设计方法。 研究开发用于超高强钢热成形FLD试验的试验方法，建立超高强钢零件热成形能力评价标准；建立连续介质损伤力学粘塑性联立本构方程，预测超高强钢热成形损伤和失效；研究车身碰撞零件热成形损伤和碰撞损伤产生机理和相互作用关系，建立损伤继承联立本构方程，实现继承成形历史的精确碰撞模拟；通过超高强钢热成形损伤预测的研究，控制、诱导零件成形损伤的产生和分布，改变车身主要碰撞零件碰撞性能，使之获得理想吸能变形和抗撞性能。 本项目将零件碰撞性能优化和热成形损伤优化相结合，实现按性能设计，按设计制造，真正做到在优化车身碰撞性能的前提下，保证轻量化的最大化。这将是车身结构轻量化和安全性设计的发展趋势和研究热点。

本研究是以汽车轻量化和安全性为目的，对超高强钢车身抗撞零件热成形损伤进行预测和控制，提出一种基于损伤控制和诱导的零件碰撞性能与成形一体化设计的技术与方法。研究开发用于超高强钢热成形FLD试验的试验方法，建立超高强钢零件热成形能力评价标准；建立基于连续介质损伤力学的粘塑性联立本构方程，预测超高强钢热成形损伤和失效；研究车身抗撞零件成形损伤和碰撞损伤产生机理和相互作用关系，建立损伤累积联立本构方程，实现继承热成形历史的精确碰撞模拟；通过超高强钢热成形损伤预测的研究，控制、诱导零件成形损伤的产生和分布，改变车身主要抗撞零件碰撞性能，使之获得理想变形吸能模式和抗撞性能。本项目将零件抗撞性能优化和热成形损伤优化相结合，实现按性能设计，按设计制造，真正做到在优化车身抗撞性能的前提下，实现轻量化的最大化。这也将是车身结构轻量化和安全性设计的发展趋势和研究热点。