Cadmium Vs. Black Oxide
Q. Which is the better coating for a fastener made from C40-UNI-7845, cadmium or black oxide?
A. Either one of these coatings will work on this type of steel, but before you choose one over the other, consider where the fastener itself will be used. Cadmium coatings offer good corrosion protection and lubricity, but they are toxic. Black oxide offers some corrosion protection but no lubricity. And while attractive, in my experience black oxide does not provide the type of corrosion protection required in difficult environmental conditions.
If you are a plater, consult with your customer about where the fastener will be used and which coating is more suitable. If you are an engineer, look at how your similar parts are coated and consider finishing these fasteners in the same way.
Why is it important for you to know this?
Masking is employed in most any metal finishing operation where only a specifically defined area of the surface of a part must be exposed to a process. Conversely, masking may be employed on a surface where treatment is either not required or must be avoided. This article covers the many aspects of masking for metal finishing, including applications, methods and the various types of masking employed.
White Bronze, Copper-Tin-Zinc Tri-metal: Expanding Applications and New Developments in a Changing Landscape
This paper deals with the renewed interest in applications for white bronze tri-metal (Cu-Sn-Zn alloy).