超声振动单点增量成形力研究
Research on Forming Force in Single Point Incremental Forming with Ultrasonic Vibration

在单点增量成形过程中，不同的工艺条件和成形力会造成接触点的应力应变状态发生较大的变化，引起板料破裂、堆积、起皱等缺陷，降低成形质量和精度。本文提出了一种基于数控技术的超声振动单点增量成形方法，通过改变工具头与成形件之间的瞬时接触状态、润滑条件以及材料的变形机理，进而降低成形力，提高成形质量。以Hass数控机床作为实验平台，设计开发了超声振动主轴以及板料夹持系统，建立了基于Kistler的成形力测试系统，通过大量成形实验，获得不同工艺和振动条件下的成形力的变化规律。
In the single point incremental forming process, the different process conditions and forming force will largely change the contact stress and strain state, sheet rupture, accumulation and wrinkling defects, finally inducing the lower forming quality and precision. An ultrasonic vibration single point incremental forming method was proposed in this paper based on the numerical control technology. This method will give rise to a lower force and a higher quality by changing the momentary contact state, lubrication condition and defromation mechanism between the tool head and the workpiece. The ultrasonic vibration spindle and sheet clamping system were designed based on the experiment platform of Hass numerical control machine and the test forming force system of Kistler was also designed. Through a large number of experiments, the forming force variation regularities under different vibration process were obtained