中文摘要：

等离子体加工技术在处理各类难加工材料的成形与制备方面备受关注，其温度特性是影响加工质量的决定性因素。针对现有温度特性研究大多在弧径向对称的假设前提下完成的问题，提出了一种基于灰度值的非对称等离子体弧温度场三维重建方法。基于灰度值对非对称等离子体弧形貌进行三维重构，重构结果与温度场的定性分布存在对应关系；利用自行设计的黑体炉对比色测温公式进行参数标定，通过比色测温原理得到等离子体弧图像中灰度值与温度的对应关系；将计算得到的温度值代入形貌模型，完成等离子体弧温度场的三维重建。研究结果描述了等离子体弧温度的分布情况，实现对非对称等离子体弧温度场的非接触测量，可为等离子体加工技术的温度控制提供指导。

英文摘要：

Plasma processing technology has been concerned in the forming and preparation of various difficult machining materials. The temperature of plasma arc is the decisive factor of influencing processing quality. The most existing studies on temperature characteristic were completed under the assumptions of arc radial symmetry. In order to solve this problem, a three-dimensional temperature reconstruction method for asymmetric plasma arc based on gray value is presented. A three-dimensional model of asymmetric plasma arc appearance which has correlation with temperature field is established based on gray value. A blackbody furnace is used to calibrate the formula of colorimetric temperature measurement. The correspondence between gray value and temperature in the image of plasma arc is obtained by colorimetric temperature measurement. Finally, the temperature value is introduced into the appearance model to accomplish the three-dimensional reconstruction for the temperature field of asymmetric plasma arc. The results show that the method can descride the temperature distribution of the plasma arc and achieve the non-contact measurement of temperature field of asymmetric plasma arc.