Temperature distribution of arc plasma based on image processing technology

With the development of modern industry, the monitoring and control of welding arc plasma is of importance than ever before. In order to capture the real-time image information of arc plasma in arc welding, the experimental system for high speed acquisition of arc plasma information is built in this paper. The experimental system is composed of high-speed camera, narrow-band filter and neural filter. The real-time image of metal argon arc welding of Q235 was captured by using high speed image system. The center wavelength of the narrow-band filter is 405 nm. The pseudo-color image and isothermal diagram of the arc plasma were obtained with software MATLAB. The radial temperature distribution of arc plasma was calculated with the Abel’s inversion. The results show that the temperature curve presents bell-shaped envelope. The maximum temperature occurs in the center of the plasma column and the value of temperature decreases gradually from the center. The experiment results lay foundation for the real-time monitoring and control of welding arc.