Journal of Sustainable Metallurgy

, Volume 4, Issue 4, pp 516–527 | Cite as

Hydrogen Reaction with SmCo Compounds: Literature Review

  • Anas Eldosouky
  • Irena Škulj
Review Article


The Hydrogen Decrepitation and the Hydrogen Disproportionation Desorption Recombination processes for the preparation and the recycling of the two industrially produced phases of SmCo alloys, SmCo5 and Sm2Co17, are reviewed. The effects of the chemical composition, the microstructure, the exposure time, the hydrogen pressure, and the temperature on the hydrogen absorption are discussed. The magnetic properties for the SmCo powder after hydrogen absorption are discussed in both the powder form and after preparing sintered or plastic-bonded magnets.


Hydrogen Decrepitation Hydrogen Disproportionation Desorption Recombination SmCo5 Sm2Co17 



The research leading to this report has received funding from the European Community’s Horizon 2020 Programme [(H2020/2014-2019)] under Grant Agreement No. 674973 (MSCA-ETN DEMETER). This publication reflects only the authors’ view, exempting the Community from any liability. Project website:

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© The Minerals, Metals & Materials Society 2018

Authors and Affiliations

  1. 1.Magneti Ljubljana, d.d.LjubljanaSlovenia
  2. 2.Jožef Stefan International Postgraduate SchoolLjubljanaSlovenia

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