Colorimetric analysis for on-line arc-welding diagnostics by means of plasma optical spectroscopy

In this paper an analysis on the suitability of employing a colorimetric analysis of the acquired plasma spectra to perform online arc-welding quality monitoring will be discussed. Different colorimetric parameters like the color temperature will be evaluated in comparison to the standard approach based on the estimation of the plasma electronic temperature. In particular, experimental tests performed with a TIG arc-welding process will show that some colorimetric parameters exhibit a better response in terms of detection and correlation to some defects than the traditional spectroscopic approach.