Coatings are put on wire for ease of drawing the wire but also to provide lubricant for the spring coilers.
Phosphate™: Gibbs Interwire trade name for soap drawn stainless
Most common and least expensive coating available
How it is applied – Soap coating is a two-step process:
First, a precoat is put on the wire in the annealed condition. Drawing soaps then adhere to the precoat during the drawing stage. Thus, the coating is composed of pre-coat and drawing soaps.
Note: Each mill uses different pre-coats and drawing soaps
Metallic premium coating
Higher cost than soap coated
Provides excellent lubricant for the spring coiler. A very consistent coating.
Can be drawn in soaps or oil
Soap-Drawn Nickel: provides more lubrication as soap will adhere to the nickel during the drawing process
Oil-Drawn Nickel: provides less lubricant but cleaner material (no soap residue)
How it works –
Nickel is put on the process wire (annealed condition) electrolytically and then drawn providing excellent adherence to the surface of the wire
Note: not all wire mills have the capability to provide this type of coating
Very little lubricant
Not typically recommended for spring coiling
Used mainly where a bright wire is needed for aesthetics (luster) and/or a functional bright finish (when surface finish, Ra, RMS, roughness can affect the performance of the end product)
Example Application: Bright Finish is standard in medical wire
How it works –
Wire is drawn in diamond dies and oil to provide the bright, lustrous finish
Note: Generally finer diameters (.030 & below) are requested in this finish in the spring temper condition
Contact Person: Ms. Florence Tang