Abstract:

In order to achieve precision bending of sheet metal using the plasma arc, forming experiments were carried on the sheet metal of 1Cr18Ni9Ti. The CMOS1303uc digital cameras and related software were used to detect the bending angle, and a closed-loop control of the forming process was established according to the detection. The experimental results show that: when the scanning number is small, the plate bending angle will be linearly increased with the increase of the scanning number. When the scanning number becomes more and more, due to thickening effect, this scanning increment of bending angle will be  decreased continuely, and the bending effectiveness reduced significantly. In order to ensure the reliability of the machining process and improve the forming efficiency, the forming process was divided into three stages according to the forming margin, and different process parameters were determined in different stages. The effective of the method was verified by the forming of bending angles 20° and 30° respectively for  stainless steel sheet.

Key words: plasma arc forming, sheet metal, bending precision, bending efficiency

摘要：

为了实现等离子电弧加热的精确弯曲成形，采用等离子电弧沿直线对1Cr18Ni9Ti不锈钢板材进行加热弯曲成形试验,并用CMOS1303uc数字相机等硬件和相关软件在等离子电弧加热弯曲成形的过程中对弯曲角度进行实时检测,实现了对成形过程的闭环控制。试验结果表明:当扫描次数较少时,板材弯曲角度随扫描次数增加近似呈线性增大;当扫描次数较多时，由于增厚效应的影响，单次扫描弯曲角度的增量会不断减小，弯曲效率明显降低。为了确保加工过程的可靠性并提高成形效率，根据加工余量的不同将成形过程分为粗、中、精三个加工阶段，各个阶段分别采用不同的工艺参数进行加工,通过弯曲角度分别为20°和30°的不锈钢薄板的成形试验验证了该方法的有效性。

关键词: 等离子电弧加热成形, 金属薄板, 弯曲精度, 弯曲效率