Correction: Non-Electrolytically Applied Zinc Coat
My response in the February issue regarding General Motors specification GMW 3359 for non-electrolytically applied zinc-rich coatings was incorrect. Here is the correct answer:
Using a non-electrolytic process greatly reduces problems associated with hydrogen embrittlement of steel components. This specification discusses the application of zinc-rich solvent or water-based coatings, typically using spray or dip-spin processes. The standard is available for a fee from engineers.ihs.com.
The dip-spin process is good for small parts and is conceptually simple. Parts are loaded into a suitable carrier, dipped into a solution and then spun at high speed to ensure that all of the components in the container are coated. The typical process sequence is: cleaning and pretreatment, coating application and oven curing, then a second coating and oven curing, if needed.
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).
Why is it important for you to know this?