点阵热源加热板料成形技术研究

Research on Sheet Warm Forming Heating with Matrix Dot Power

初步试验验证板料温成形中,采用离散化热源和均匀热源相比能够进一步提高板料成形性能的基础上,提出点阵热源加热板料温成形新技术。基于有限元仿真,采用0Cr18Ni9不锈钢板料对点阵热源加热成形过程进行验证和初步研究。研究结果表明,点阵热源加热板料成形工艺是完全可行的,在相同热量的情况下,通过控制点阵热源的分布可以得到比均匀热流加热更大的极限拉深比;采用点阵热源加热拉深得到的零件壁厚分布一般存在两个明显的谷值,第一个谷值点在凸模圆角处,和最大拉深力有关,第二个谷值点在零件直壁上,是由于凸缘部位的高温材料拉深成直壁变成传力区以后因温度高承载能力下降引起的。

A new method, named warm forming of lightweight sheet materials heated by matrix dot power is proposed after a validation that formability improvement can be achieved during sheet forming heating with matrix dot power compared with normar power. Using 0CrlSNi9 sheet this new method is validated and preliminarily studied with assistance of FE software Marc. The result shows that the new process of sheet warm drawing process using dot matrix power is feasible, and through controlling the distribution of dot power a higher limiting drawing ratio compared with warm deep drawing using normal power can be obtained. There are two key points where the wall thickness is quite small, and the first lying near punch corner caused by the peak values of the punch force, the second being located in the wall of formed cups caused by carrying capacity decreasing of this point because of temperature rising.