What are they made from?
Our snaps are made from nickel plated steel, solid brass, chrome plated brass, or stainless steel. NOTE: We do not use or sell die cast zinc snaps Find out why here… Our highest quality snaps in terms of strength and corrosion resistance are stainless steel. Our most lustrous finish is chrome plated brass.
|Comparison of metals|
|Metal||Ultimate Tensile Strength (MPa)||Corrosion Resistance|
|Zinc Die Cast (Zamak 3) 1||268||good|
|Carbon steel (AISI 1018)1||440||poor unplated
good if nickel plated
|Stainless Steel (AISI 316) 1||585||excellent|
|Stainless Steel (AISI 302) 1||800||very good|
1 Zinc, steel and stainless steel have many formulations. These examples are typical.
What is Carbon Steel?
Carbon steel is steel in which the main alloying constituent is carbon in the range of 0.12–2.0%. Mild steel, also called plain-carbon steel, is the most common form of steel because its price is relatively low while it provides material properties that are acceptable for many applications, more so than iron. Mild steel has a relatively low tensile strength, but it is cheap and malleable. Exposed mild steel rusts readily. Nickel plating is an excellent rust inhibitor. Rust will occur whenever damage or scratches expose the underlying steel.
What is Brass?
Brass is an alloy made primarily of copper and zinc. Basic modern brass is 67% copper and 33% zinc. With a bright gold appearance, it is more malleable that zinc die cast. It is easier to cast to a fine finish than zinc die cast. Therefore, it yields a deeper more lustrous sheen when buffed or nickel plated. Over time the copper component in brass will oxidize into a greenish or bronzy-brown vertigris or patina.
Vertigris provides a protective coating that will not rust further. Occasional polishing can remove vertigris. Nickel plating over brass is quite common. An additional coat of chrome over the nickel produces a very deep and lustrous finish as well as providing additional protection from vertigris.
What is Stainless Steel?
The addition of a minimum of 12% chromium to steel makes it resist rust, or stain ‘less’ than other types of steel. The chromium in the steel combines with oxygen in the atmosphere to form a thin, invisible layer of chrome-containing oxide. If the metal is cut or scratched and the passive film is disrupted, more oxide will quickly form and recover the exposed surface, protecting it from oxidative corrosion. Its natural finish when polished is very shiny though not as lustrous as high quality nickel plate. It is the best option when seeking quality, longevity, absolutely perfect performance, and easy maintenance & cleaning.
Why Don’t We Use Die Cast Zinc Snaps?
Die cast zinc, or zinc diecast, is a casting of zinc with small amounts of copper, aluminum, and magnesium. Zinc diecast, because it is extremely easy to cast at moderate temperatures, is the most commonly used metal for casting automotive, household or general hardware. Zinc diecast is brittle and lacks sufficient malleability to meet our standards. When it fails it does so catastrophically. It has less than 1/2 the tensile strength of brass and less than 1/3 the tensile strength of stainless steel (AISI 302). It often contains a number of impurities and can be prone to pitting and roughness. As such the quality of the surface can make it difficult to achieve a high quality plated finish. While zinc diecast is quite corrosion resistant, where condensation forms on the surface and remains there for extended periods, a conspicuous form of white corrosion resembling ‘white rust’ forms.