Stainless Steel and Music Wire
Stainless steel is an alloy somewhat similar to ordinary steels except that it contains from 12 to 20 percent chromium which makes it completely resistant to atmospheric corrosion. Stainless steel and music wire are the two most commonly used materials in spring manufacture.
Music wire is the best-quality, most generally used cold-drawn high-carbon spring steel. It has a high tensile strength, high elastic limit, and can withstand high stresses under repeated loadings. This type of wire is also called "piano wire", because of it's use in stringed instruments, especially the piano.