What Are The Differences Between 302 and 316L Stainless Steel Shims?

What Are The Differences Between 302 and 316L Stainless Steel Shims?

Metal shims are produced in grades 302 and 316L stainless steel. This article looks at what makes them different from each other.

Chemical Composition

302 stainless steel contains higher levels of carbon and chromium compared to 316 stainless steel, with carbon values reaching up to 0.15% compared to 0.08% for 316L stainless steel. Chromium levels of 302 stainless steel are at 17% compared to 16% for 316L stainless steel.

Hardness

302 stainless steel shims are Full Hard, with Rockwell Hardness ratings ranging from 40 to 45 on the C Scale. This hardness allows 302 stainless steel shims to be used widely in applications requiring high strength such as compression springs and custom cut parts.

316L stainless steel shims are on the other hand, annealed, making them more ductile but less hard. This gives them a Rockwell Hardness rating of about 95 on the B Scale.

Tensile Strength

302 stainless steel shims have higher tensile strength than 316L stainless steel shims, having a rating of 185,000 psi compared to 70,000 for 316L stainless steel shims.

Yield Strength

302 stainless steel shims also have higher yield strength than 316L stainless steel shims, having a rating of 140,000 psi compared to 25,000 for 316L stainless steel shims.

Corrosion Resistance

Both 302 and 316L stainless steel shims are considered to be extremely resistant to corrosion caused by solvents, cleaning solutions and acids. However, 316L stainless steel shims have the added advantage of being resistant to corrosion caused by salt or sea water. This makes them popular for use in the marine and oil and gas industries.

Price Comparison

Here comes the most important difference: Which is more expensive? 316L is generally more expensive compared to 302 stainless steel shims; the extent of which varies depending on the thickness. A comparison of two shim rolls with 0.25mm thickness shows a price difference of 30%. For thickness .002”, the difference is less than 1%.