フェロキシル試験によるステンレス鋼の耐銹性評価 [in Japanese] Evaluation of Rust Resistance of Stainless Steels by Applying the Ferroxyl Test [in Japanese]
Access this Article
Search this Article
A method for evaluating the rust resistance of stainless steels by applying the ferroxyl test was investigated. Filter paper is moistened with test solution containing Fe(CN)<sub>6</sub><sup>3-</sup> and Cl<sup>-</sup> ions. The paper is then superimposed on a sample for 3 to 10 minutes. This induces pitting corrosion on the sample's surface. Iron ions generated by corrosion react with Fe(CN)<sub>6</sub><sup>3-</sup> ions to produce blue precipitates of prussian blue, Fe<sub>4</sub>[Fe(CN)<sub>6</sub>]<sub>3</sub>, which form blue spots on the filter paper. After the filter paper is rinsed and dried, rust resistance is evaluated based on the ratio of the total area of blue spots. The time required for this test is only 15 to 20 minutes and the method is very simple. It also has strong correlativity with the atmospheric exposure test on the evaluation of rust resistance of bright annealed ferritic stainless steels. It should also be noted, however that the method cannot predict the deterioration of rust resistance in every steel having a different surface film and roughness induced by atmospheric exposure. In conclusion, the method is most useful for quality control in a manufacturing process or the product inspection.
- Jitsumu Hyomen Gijutsu
Jitsumu Hyomen Gijutsu 47(10), 873-879, 1996-10
The Surface Finishing Society of Japan