Hastelloy G 35 сorrosion tests for intergranular corrosion resistance

Issue 26(2) 2021
Pages 27-31

J.F. Gordeeva, Sverdlovsk Research Institute of Chemical Engineering, Yekaterinburg, Russian Federation
E.S. Filatov, The Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences, Yekaterinburg, Russian Federation
A.S. Derbyshev, Sverdlovsk Research Institute of Chemical Engineering, Yekaterinburg, Russian Federation
V.Ya. Kudyakov, The Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences, Yekaterinburg, Russian Federation


Keywords: corrosion, Hastelloy G 35, provoking heating, intergranular corrosion, corrosion rate

doi: 10.31615/j.corros.prot.2021.100.2-2

 

The article is devoted to the analysis of corrosion behavior and assessment of the resistance of Hastelloy G 35. Nickel-based alloys (steels) containing chromium, molybdenum, tungsten, possibly iron are widely used as materials for the manufacture of equipment in high-temperature technological processes using solutions of highly hygroscopic halides (chlorides) in molten halides (chlorides) of alkali metals. During the operation of the equipment, the instability of the surface of apparatus and pipelines to corrosion is determined. In this test, 4 samples of 80×20×3 mm were used, of which 2 samples were subjected to provoking heating, and 2 samples were examined in their normal state. Our tests were carried out in a boiling aqueous solution of iron sulfate and sulfuric acid for 48 ± 0.25 h. Further, the bent samples were examined using an MBS-9 microscope with a magnification of х8. The results of corrosion tests are also presented. As a result of the study, the rate of penetration of corrosion of the alloy was calculated. Hastelloy microstructure is presented. The average depth of destruction was determined from the six maximum values detected in six fields of view. According to the research results, the corresponding conclusions were made.