On the hydrogen state in magnesium alloys after corrosive effect

Keywords: magnesium alloys, corrosion, hydrogen in metals, advanced materials

Abstract

Low resistance to corrosion and stress corrosion cracking (SCC) hinders the widespread introduction of the magnesium alloys as the construction materials. Considered, that the SCC of the magnesium alloys may be related to the hydrogen fragility. Nevertheless, at the moment, the role of hydrogen in the SCC mechanism of magnesium alloys is not fully evident. In the previous papers, the authors identified that the role of diffusion-active hydrogen in the SCC process of magnesium alloys is highly doubtful: the results both of mechanical tests and gas analysis show that the concentration of diffusion-active hydrogen in tested materials is negligibly small; normally, hydrogen locates in the corrosion products. However, these studies have not identified the influence of external strains on the concentration and state of hydrogen, therefore, it is not clear if the results obtained are typical for SCC only or valid for the corrosion without external load. In this context, the authors set the goal to identify the concentration and the state of hydrogen in magnesium alloys after corrosive action without external strains. Samples of MA14 and MA2-1 alloys and pure magnesium were exposed in a corrosive medium, after which, each sample was divided into two parts: the corrosion products were removed from the first part and left untouched in the second part. Next, the authors studied the samples by gas analysis; and obtained extraction curves and hydrogen concentration values for each of them. The results of the study showed that the removal of corrosion products leads to a strong decline of hydrogen concentration, and at temperatures below 300 °C, it practically ceases. This indicates that most of the hydrogen is in the corrosion products and not in the diffusion-active form in the matrix metal, which is similar to the results obtained when studying the SCC.

Author Biographies

Pavel N. Myagkikh, Togliatti State University, Togliatti (Russia)

technician of the Research Institute of Advanced Technologies, postgraduate student

Evgeny D. Merson, Togliatti State University, Togliatti (Russia)

PhD (Physics and Mathematics), senior researcher of the Research Institute of Advanced Technologies

Vitaly A. Poluyanov, Togliatti State University, Togliatti (Russia)

junior researcher of the Research Institute of Advanced Technologies

Dmitriy L. Merson, Togliatti State University, Togliatti (Russia)

Doctor of Sciences (Physics and Mathematics), Professor, Director of the Research Institute of Advanced Technologies

Aleksey Yu. Vinogradov, Togliatti State University, Togliatti (Russia); Norwegian University of Science and Technology, Trondheim (Norway)

PhD (Physics and Mathematics), Deputy Director of the Research Institute of Advanced Technologies, professor of Chair of Mechanical and Industrial Engineering

References

Chakrapani D.G., Pugh E.N. Hydrogen embrittlement in a Mg-Al alloy. Metallurgical Transactions A, 1976, vol. 7, no. 2, pp. 173–178.

Chen J., Wang J., Han E., Dong J., Ke W. States and transport of hydrogen in the corrosion process of an AZ91 magnesium alloy in aqueous solution. Corrosion Science, 2008, vol. 50, no. 5, pp. 1292–1305.

Kappes M., Iannuzzi M., Carranza R.M. Hydrogen Embrittlement of Magnesium and Magnesium Alloys: A Review. Journal of the Electrochemical Society, 2013, vol. 160, no. 4, pp. C168–C178.

Zhou L.F., Liu Z.Y., Wu W., Li X.G., Du C.W., Jiang B. Stress corrosion cracking behavior of ZK60 magnesium alloy under different conditions. International Journal of Hydrogen Energy, 2017, vol. 42, no. 41, pp. 26162–26174.

Atrens A., Dietzel W., Srinivasan P.B., Winzer N., Kannan M.B. Stress corrosion cracking (SCC) of magnesium alloys. Stress corrosion cracking: Theory and practice, 2011, pp. 341–380.

Atrens A., Winzer N., Dietzel W. Stress corrosion cracking of magnesium alloys. Advanced Engineering Materials, 2011, vol. 13, no. 1-2, pp. 11–18.

Winzer N., Atrens A., Song G., Ghali E., Dietzel W., Kainer K.U, Hort N., Blawert C. A critical review of the Stress Corrosion Cracking (SCC) of magnesium alloys. Advanced Engineering Materials, 2005, vol. 7, no. 8, pp. 659–693.

Winzer N., Atrens A., Dietzel W., Song G., Kainer K.U. Evaluation of the delayed hydride cracking mechanism for transgranular stress corrosion cracking of magnesium alloys. Materials Science and Engineering A, 2007, vol. 466, no. 1-2, pp. 18–31.

Choo W.Y., Lee J. Thermal analysis of trapped hydrogen in pure iron. Metallurgical transactions A. Physical metallurgy and materials science, 1982, vol. 13A, no. 1, pp. 135–140.

Merson E.D., Myagkikh P.N., Klevtsov G.V., Merson D.L., Vinogradov A. Effect of fracture mode on acoustic emission behavior in the hydrogen embrittled low-alloy steel. Engineering Fracture Mechanics, 2019, vol. 210, pp. 342–357.

Lynch S.P. Hydrogen embrittlement phenomena and mechanisms. Corrosion Reviews, 2012, vol. 30, no. 3-4, pp. 105–123.

Merson E.D., Myagkikh P.N., Poluyanov V.A., Merson D.L., Vinogradov A. On the role of hydrogen in stress corrosion cracking of magnesium and its alloys: Gas-analysis study. Materials Science and Engineering A, 2019, vol. 748, pp. 337–346.

Myagkikh P.N., Merson E.D., Poluyanov V.A., Merson D.L., Vinogradov A.Yu. The state of hydrogen and its role in the mechanism of stress corrosion cracking of magnesium alloys MA2-1 and MA14. Sbornik tezisov Mezhdunarodnogo simpoziuma “Perspektivnye materialy i tekhnologii”. Vitebsk, 2019, pp. 230–232.

Poluyanov V.A., Merson E.D., Myagkikh P.N., Merson D.L., Vinogradov A.Yu. Effect of corrosion products, pre-exposure time in a corrosive environment and strain rate on the mechanical properties and fracture mechanism of MA14 alloy in air tests. Sbornik tezisov Mezhdunarodnogo simpoziuma “Perspektivnye materialy i tekhnologii”. Vitebsk, 2019, pp. 402–404.

Kamilyan M., Silverstein R., Eliezer D. Hydrogen trapping and hydrogen embrittlement of Mg alloys. Journal of Materials Science, 2017, vol. 52, no. 18, pp. 11091–11100.

Morozova G.I. Phase composition and corrosion resistance of magnesium alloys. Metal Science and Heat Treatment, 2008, vol. 50, no. 3-4, pp. 100–104.

Tuchscheerer F., Krüger L. Hydrogen-induced embrittlement of fine-grained twin-roll cast AZ31 in distilled water and NaCl solutions. Journal of Materials Science, 2015, vol. 50, no. 14, pp. 5104–5113.

Ono K., Meshii M. Hydrogen detrapping from grain boundaries and dislocations in high purity iron. Acta Metallurgica Et Materialia, 1992, vol. 40, no. 6, pp. 1357–1364.

Cai L., Zhao L. Effect of hydrogen trapping and poisons on diffusion behavior of hydrogen in low carbon steel. Key Engineering Materials, 2018, vol. 764, pp. 3–10.

Klyamkin S.N. Metal hydride compositions on the basis of magnesium as materials for hydrogen accumulation. Russian Journal of General Chemistry, 2007, vol. 77, no 4, pp. 712–720.

Published
2020-03-28
Section
Technical Sciences