This article investigates the ability of using plasma machining for cutting simultaneously two parallel thin layers at different gap distances. The main aim of this work is to identify whether this technology if mechanized can be more appropriate than using a circular saw to process a three-dimensional structure material such as double layers, box sections or rails. This research is aimed at those working in the automotive industry and converting vehicles. Test models were built for the experiments using 0.7 mm thick steel sheets DCO1 grade, similar material used for some underbody vehicle chassis parts. Serie of cuts were carried out first to analyze the ability of the plasma to perform a simultaneous cutting in two separate sheets with an air gap, followed by tests to minimize the deformation and heat affected zones on the top sheets adopting Taguchi methodology. Parameters analyzed included cutting speed, intensity, pressure, and gap distance between the two sheets. The specimens collected were assessed for quality including Kerf, dross, hardness, offset distance between the top and bottom cut edge, sheet deformation and heat affected zones. The experiments showed the possibility to use plasma to cut in more than one sheet with one pass even if layers are separated with air distance. Analysis of variance showed that the input-controlled parameters which had the most influence on the top sheet deformation and HAZ were respectively intensity and gap. Regression equations showed a good model fit and the relationship between the input and output variables were strong. Results revealed that plasma could be an alternative tool if optimized to process three-dimensional structure parts, but it is dependent on the tolerances and the quality required.

本文研究了使用等离子加工以不同的间隙距离同时切割两个平行薄层的能力。这项工作的主要目的是确定如果机械化的这项技术是否比使用圆锯处理三维结构材料（例如双层，箱形截面或钢轨）更合适。这项研究的对象是从事汽车行业和改装车辆的人员。使用0.7毫米厚的DCO1级钢板为实验建立了测试模型，类似的材料用于某些车身底部底盘部件。首先要进行一系列的切割，以分析等离子体在两个有气隙的单独薄片中同时切割的能力，然后通过Taguchi方法进行测试，以最小化顶板上的变形和受热影响区域。分析的参数包括切割速度，强度，压力和两张纸之间的间隙距离。对收集的样品进行质量评估，包括切缝，浮渣，硬度，上下切边之间的偏移距离，板材变形和热影响区。实验表明，即使层与空气之间的距离分开，也可以使用等离子通过一遍切割多于一张的可能性。方差分析表明，对表层变形和热影响区影响最大的输入控制参数分别是强度和间隙。回归方程显示出良好的模型拟合，并且输入和输出变量之间的关系很强。