The Reclamation of Improperly Cadmium Electroplated High Strength Steel Parts

摘要

Circumferentially notched round specimens of 4340 type steel were cadmium plated in a galvanic bath known to be embrittling. The specimens were reclaimed by stripping and baking. Half the specimens were replated in a nonembrittling bath. Specimens were subjected to a sustained load. If failure had not occured within 1000 HR, the load was raised to a higher level for another 1000 HR and so on until failure occured. Fractography was performed on specimens experiencing delayed and fast fracture. Reclamation does not remove all traces of hydrogen embrittlement, but raises the threshold stress to such a level that hydrogen embrittlement is no longer a hazard under normal circumstances.