SUPER STEEL: Higher grades of stainless are stronger and more resistant to corrosion

摘要

It would be hard to find a metal or metal alloy today that is more widely used in the marine industry than stainless steel. Most stainless steel is so-called 18-8, primarily type 304. Two other stainless steel grades used on a lot of boats are types 316 and 317. The 18-8s get their name from their chemical composition: 18 percent chromium and 8 percent nickel. Some 70 to 80 percent of the stainless steel fittings and hardware you'll find in marine stores and chandleries are 18-8 grades. Eigh-teen-eights have good mechanical properties with yield strengths ranging from 35,000 to 42,000 pounds per square inch and are readily cut, bent and formed by common fabrication methods.