Pre-treatment and electroplating of especially low alloyed high tensile strength steel components can be followed by a delayed hydrogen-induced fracture known as hydrogen embrittlement. The entire coating process has to be controlled to avoid any failure. As estimated by the fracture behaviour of differently prepared samples using a special constant load test, atomic hydrogen being evolved during the coating process and penetrating into the base metals is mainly trapped close to the interface base/metal-coating. During a baking procedure after plating the atomic hydrogen can be removed from the traps and effuse through the coating the same time being more homogeneously distributed in the bulk of the base metal, both reducing the risk of embrittlement. This effect seems to be evident by tensile tests (sustained load tests and incremental step load tests) and has been proven by localized glow discharge emission optical spectroscopy (GD-OES). Now quantitative and localized analysis of hydrogen is possible as certified reference materials have been developed. The results give an improved knowledge and enable one to work out process parameters and test procedures for coating techniques to be more effective to avoid hydrogen embrittlement. Examples will be discussed.
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