Monday, September 10, 2012

Stainless Steel Grades, Applications and Magnetic Compounds

Today, we will look at different grades of stainless steel 18/8, 304, A2, 316, A4 and 410 that are magnetic and non magnetic, or so they say.  I am emailed all of the time "Why is this bolt magnetic?"  Most common grades of stainless steel are magnetic in some degree.  In fact, all of the stainless steel coming into the USA from china and other countries are magnetic in some form.  18/8, 304, A2 and 410 are more magnetic then 316 or A4 stainless steel.  The most common grade of stainless steel is 304, or as referred to 18/8, and in metric A2.  The second most common grade is 316 which is used in salt water application marine grade, food prep equipment, surgical, medical and pharmaceutical applications.  316 Stainless steel is used in these areas to minimize metallic contamination.  316 stainless is used in marine applications due to its increased resistance to chloride corrosion compared to 304, 18/8, A2 or 410 stainless steel.  Also most high end watches are made with 316 stainless.  410 Stainless steel is used in most construction fasteners when a high strength iron chromium water resistant product is required, but less corrosion resistant to water.


  • 18/8, 304 and A2 are used in most common construction projects, telecom, car, truck and trailer restoration, playgrounds that are exposed to the elements of natural rain water.  These grades are all magnetic. Here is a sample of 304 18/8 Stainless Steel
  • 316 And A4 are used in food prep manufacturing equipment, salt water marine application, surgical and pharmaceutical equipment and products.  Watches are made from 316 or A4 stainless steel.  Partially magnetic.  Here is a sample of 316 Stainless Steel
  • 410 Is used in most construction fasteners in exterior application exposed to the elements.  These fasteners are used in standard rain water application where there is no salt water exposure.  410 are magnetic.  Here is a sample of 410 Stainless Steel