Corrosion of Stainless Steels 2

[slv122]

i need to know, what is the most corrosive resistent stainless steel. we are debating between 316 and 304. 316 is subject to more pitting and crevice corrosion. also what is the best method of testing them. we need to determine about how long they will go without corroding.
as to what we plan to use this for, it is used to hold gears in a water motor that run a lawn sprinkler. it will be in a water motor that will be submerged in water (all types) for lenghts of time. i read that the sea water (fog) test is the best method. i also need to know if this test is best and how long should you run this test for.

 

[TVP]

You have received several responses to this question, so I am just going to summarize some things, and offer you some potential test methods. First, Type 316 stainless is more resistant to corrosion than Type 304, including pitting and crevice corrosion. There is an absolutely gigantic database with regards to these two materials, as they have been tested extensively in a wide variety of corrosion environments.

You would benefit from learning more about stainless steel and corrosion. Various websites to visit include:

http://www.stainlesscenter.com

http://www.nidi.org

http://www.ssina.com

There are a number of good reference books available from ASM International that cover stainless steel and corrosion. Specifically, you should investigate the following:

ASM Specialty Handbook: Stainless Steels

ASM Handbook Volume 01: Properties and Selection: Irons, Steels, and High-Performance Alloys

Introduction to Stainless Steels

ASM Handbook Volume 13: Corrosion

You can obtain these books from ASM at

http://www.asminternational.org

and then click on BOOKSTORE

The following is a list of ASTM test methods related to corrosion testing. You can obtain these standards from ASTM International at

http://www.astm.org

:

ASTM G 31 Standard Practice for Laboratory Immersion Corrosion Testing of Metals

ASTM G 48 Standard Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride Solution

ASTM G 78 Standard Guide for Crevice Corrosion Testing of Iron-Base and Nickel-Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environments

ASTM B 117 Standard Practice for Operating Salt Spray (Fog) Apparatus

 

[joescan]

3 articles here that should help

http://www.azom.com/details.asp?ArticleID=1177

http://www.azom.com/details.asp?ArticleID=1146

http://www.azom.com/details.asp?ArticleID=470