中文摘要：

介绍汽车轻量化的途径及内高压成形技术的应用趋势。阐述管材内高压成形基础理论、工艺模具关键技术以及产业化应用方面的最新进展。在内高压成形基础理论方面,揭示弯曲管内高压成形的环向应力、轴向应力及环向应变、轴向应变和厚向应变的分布规律。阐明内高压整形阶段圆角充填时存在极限圆角半径,并分析液体压力和摩擦条件对极限圆角半径的影响规律。在工艺模具关键技术方面,提出降低成形压力的内凹预制坯方法和大径厚比超薄异型管件内高压成形方法,解决多孔同步液压冲孔模具等关键技术。在工业应用方面,攻克超高压建立、高压水介质传输、超高压与多轴位移闭环实时控制等多项设备关键技术,为国内汽车主机厂及零部件厂研制了多台生产用大型内高压成形机,成功应用于奔腾轿车副车架、扭力梁和SUV车前支梁等汽车零部件的批量制造。

英文摘要：

Lightweight ways of automotive and application trends of tube hydroforming are introduced.Latest progresses and achievements in fundamental theories,key processes and tools and industrial applications of tube hydroforming are illustrated.In fundamental theories aspect,circumferential stress,axial stress,circumferential strain,axial strain and normal strain states of curved tubular components in hydroforming process are disclosed.The existence of limited corner radius in calibration process is clarified and the effect of internal pressure and friction on limited corner radius is analyzed.In key processes and tools aspect,the methods that the calibration pressure is reduced by the petal-like preform shapes and that the large diameter and ultra thin thickness tube is hydroformed integrally are proposed.Key technologies on hydro-piercing processes and tools with multiple holes synchronously are solved.In industrial applications aspect,key technologies on facilities are solved for extra high pressure establishment,high water media transmission,real-time and closed loop control system of extra high pressure and multiple spindle displacements.Several hydroforming machines are developed for automotive factories and automobile accessories factories in mass production of typical parts,such as engine cradle,torsion beam and front beam holder.