Reducing Double Handling of Plated Fasteners that Require Baking and Passivating
Mark Adams, Technical Account Manager, Columbia Chemical Corporation
There is a common challenge faced by many acid zinc platers who perform hydrogen embrittlement relief on fasteners while needing to adhere to the requirements of a corrosion resistance spec: double handling of parts.
Often, when running a barrel line with fasteners, if the company running the line bakes after passivating, it will experience salt spray failures and end up having to zinc plate, bake, activate (flash or nitric) and then passivate in order to get the corrosion protection needed. The ideal process would instead be to zinc plate, passivate and then perform the hydrogen embrittlement relief step without the need to double handle parts.