Hydrogen high strength steel

During the electrodeposition of zinc or cadmium on high strength steel, hydrogen is produced at the cathode and some of it will dissolve into the substrate. As a result, cracks may form spontaneously some time after the plated objects have been removed from the electrolyte. To avoid such delayed cracking, the plated objects must be heat treated, in order to allow the hydrogen to escape from the metal. 

D. Berman, "Effect of Baking and Stress on the Hydrogen Content of Cadmium Plated High Strength Steels," paper 192 presented at Corrosion 85 NMCE, Materials Peformance, Boston, Mass., Sept. 1985. 

There has been some controversy as to whether s.c.c. occurs by active path corrosion or by hydrogen embrittlement. Lack of space does not permit a full treatment of this subject here. References 14 and 15 are recent reviews on the s.c.c. of high strength steels and deal with the mechanism of cracking (see also Section 8.4). It is appropriate to discuss briefly some of the latest work which appears to provide pertinent information on the cracking mechanism. It should be noted, however, that cracking in all alloy systems may not be by the same mechanism, and that evidence from one alloy system need not constitute valid support for the same cracking mechanism in another. 

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