Electrochemical pretreatment as well as plating processes of especially low alloyed high strength steels can be followed by hydrogen embrittlement. Damages may occur particularly with unfavourable values of the surface/volume ratio and conditional on the hardening conditions of the components. This is the case for conventional zinc plating but also for new zinc alloy coatings often used as replacement for cadmium. In this paper especially the long delay embrittlement behaviour of Znplated fuse holder rings was investigated. This phenomen can be significantly correlated with the pickling procedure and the post coating heat treatment. However further influence concerning the surface roughness, texture and morphology of the components can be observed. The mechanism seems to be of electrochemical nature influencing the rate of atomic hydrogen evolution during the plating process. A test procedure for evaluated long delay embrittlement has been developed.
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