304 Stainless Steel vs. 316 Stainless Steel - What is the difference?

From a chemical or scientific standpoint the answer would be that 304 stainless steel contains 18% chromium and 8% nickel while 316 contains 16% chromium, 10% nickel and 2% molybdenum. The molybdenum is added to help resist corrosion.

Type 304, with its chromium-nickel content and low carbon, is the most versatile and commonly used of the austenitic stainless steels. Type 304 proves to be resistant to oxidation, corrosion, and durability. Type 304 stainless provides ease of fabrication and cleaning, prevention of product contamination and offers a variety of finishes. Type 304 stainless steel is used in enclosures, storage tanks, pressure vessels and tubing or piping.

Type 316 stainless steel is an austenitic chromium-nickel stainless and heat-resisting steel with superior corrosion resistance as measured up to other chromium-nickel steels when exposed to many types of chemical corrodents. Buyers may find that the upfront cost is a little higher but could save alot on the backend which is something to keep in mind when purchasing.

Given that Type 316 stainless steel alloy contains molybdenum it has a considerable more resistance to chemical attack than 304. Type 316 is durable, easy-to-fabricate, clean, weld and finish. It is considerably more resistant to solutions of sulfuric acid, chlorides, bromides, iodides and fatty acids at high temperature. Stainless steels containing molybdenum are required in the manufacture of certain pharmaceuticals in order to avoid excessive metallic contamination.