On-line Analyzer for Ni–Zn Alloy Electroplated Coating on Steel

The Ni–Zn electroplated steel sheet is used as a car body material because of its high corrosion resistance. On production of this sheet, the coating weight and Ni content of the alloy coating are necessary to be controlled to ensure the quality of the products. An on-line X-ray fluorescence analyzer has been developed for the determination of the coating weight and Ni content of the alloy coating. The features of the analyzer are summarized as follows: (1) The analysis is carried out full automatically. (2) X-ray intensities are measured by a detector (ionization chamber) with an Fe filter and the other with a Ni filter. The coating weight and the Ni content are calculated from the intensities measured by the two detectors. (3) This analyzer has been operated for seven years without any trouble.