Large oven with temperature recorder.

Embrittlement Relief

Electroplating processes take place in an aqueous solution, and hydrogen gas is liberated at the cathode as the current flow supplies electrons to the hydrogen ions in solution. When hydrogen enters hardened steel, it can cause a loss of ductility, a loss of load carrying ability, and/or microscopic cracks and failures at applied stresses below the normal design strength of the steel.

Steels that have been heat treated to a hardness of Rockwell C31 or higher are at greatest risk of embrittlement. During pre-electroplating, the cleaning and certain pickling solutions are also apt to introduce hydrogen into the steel.

The accepted method to alleviate hydrogen embrittlement is a process called relief baking or embrittlement relief baking. The process typically requires baking be done immediately after processing. A reference specification, AMS-27559/9, covers "Hydrogen Embrittlement Relief (Baking) of Steel Parts".

Curing & Adhesion Baking

Baking is also used to accelerate cure of Teflon coatings and to cure some types of maskants. Adhesion baking is used to improve adhesion of duplex plated parts.