On the Surface Analysis of Steel Sheet by Fluorescent X-ray

Abstract

A quantitative analysis of sticking materials on steel sheet surface was made possible by fluorescent X-ray according to a following method.
1. Preparation of standard samples:
A known quantity of standard solution of element to be analyzed was placed on steel sheet in area where X-ray irradiated and then dried. The quantity of the placed element divided by the area was called “sticking density”.
2. Drawing of calibration curves:
Differences of X-ray counting rates after and before placing standard solution were plotted against sticking densities and calibration curves were drawn.
3. Precisions and lower limits of determination:
For example, standard deviation was 0.0148μg/cmcm² for Na at 0.566μg/cmcm² and 0.0048μg/cmcm² for Cl at 0.252μg/cmcm².
Lower limit was 0.121μg/cmcm² for Na and 0.038μg/cmcm² for Cl.
Conclusively, determination of sticking soil-materials on steel sheet surface which caused to rust initiation and films produced by chemical treatments were made possible without establishment of a chemical analysis method.