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Specs, symbols, and markings for stainless fasteners?

Hello my name is Shawn, I have a couple of questions. I deal with a lot of stainless steel and aluminum. We have several different types of bolt that put together our product. Recently I notice a slight change in the socket head cap screws which we are receiving. Simply, color of the bolts. They are variable sizes 1/4 x1/2 all the way up to 2 1/2 inch. The bolt did not have any markings on it. Some had f s on the head. The package came with 18-8 on it. My thought on that is that it is a low grade ss. If you have any info or reference where I could look up specs and marking that would be great. Thank you for taking the time to read this.

Sincerely,

Shawn Fortier
wakeboarding industry - Edmonton, Alberta, Canada
2003

18-8 is equivalent to a 304 grade of stainless steel. One of the least expensive among the austenitic ones.

Guillermo Marrufo
Monterrey, NL, Mexico
2003

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18-8 (304) stainless steel is a very good grade of stainless steel, but not the best. It is austenitic, but not very resistant to chlorides or salt spray.

To find a list of grades of stainless steel and what they contain you can get the ASTM book "Metals and Alloys in the Unified Numbering System". Or, you can go online and do some searching. An EXAMPLE of this would be http://www.askzn.co.za/tech/tech_grades.htm or: http://www.avestapolarit.com/upload/documents/technical/datasheets/AvP-120%20europe.pdf There are many other good sites.

Lee Kremer
Stellar Solutions, Inc.

McHenry, Illinois

2003