Colorimetric tests as a new method for analysis of the corrosion resistance of bare and phosphated steel in 3.5% NaCl solution

This article proposes the use of colorimetric parameter from spectrophotometric test, a new inspection technique, for nondestructive surface corrosion monitoring. It presents a corrosion test conducted over 7 days, for bare and phosphated steel to obtain color parameters of corrosion solution by using spectrophotometric test. The values are presented as lightness versus time graphs. Then, this method was comprised with weightloss method as an conventional test for calculating corrosion rate of metal. The results show that the technique is feasible as a new method to check the surface corrosion damage state.

Keywords:

Corrosion , Colorimetric values , Spectrophotometric tests , Phosphated conversion coating