Crevice corrosion testing, stainless alloys

Nagaswami, N. S. and Streicher, M. A., Accelerated Laboratory Tests for Crevice Corrosion of Stainless Alloys, Paper 71, NACE CORROSION/83 Conference, NACE, Anaheim, CA, 1983. 

Guide for Crevice Corrosion Testing of Iron-Base and Nickel-Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environments, G 78, Annual Book of ASTMStandards, ASTM, 1992, p 463-470... 

Several tests have been developed over the years to determine the crevice corrosion resistance of alloys. The objectives of these tests include comparison of alloys, qualification of alloys for a given service, evaluation of the effects of fabrication processes on crevice corrosion resistance, quality control, and life prediction. This chapter will briefly describe the types of tests, and their applicability and limitations, with a focus on tests that have been or are now being considered by ASTM Committee G-1 on Corrosion of Metals. While these test principles are applicable to a wide variety of alloys, the information presented is focused on stainless and nickel-base alloys. 

ASTM G 78, Guide for Crevice Corrosion Testing of Iron Base and Nickel Base Stainless Alloys in Seawater and Other Chloride-Containing Aqueous Environment, descrihes the use of multiple crevice assemblies and other devices applicable to nickel alloy testing in chloride environments. These procedures can be used to identify conditions most likely to result in crevice corrosion and provide a basis for assessing the relative resistance of various alloys to crevice corrosion under certain specified conditions. 

Use alloys resistant to crevice corrosion, such as titanium or Inconel. Increased Mo contents (up to 4.5%) in austenitic stainless steels reduce the susceptibility to crevice corrosion. Use appropriate alloy after prescribed service tests for a specific application. 

Recommended practice for examination and evaluation of pitting corrosion Test method for determining susceptibility to stress corrosion cracking of high-strength aluminium alloy products Test method for pitting and crevice corrosion resistance of stainless steels and related alloys by the use of ferric chloride solution Recommended practice for preparation and use of direct tension stress corrosion test specimens... 

A common chemical laboratory test for corrosion resistance is a simple exposure test using metal coupons. The ASTM standard G48 —Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys by Use of Ferric Chloride Solution—describes a simple exposure test. The material coupons (e.g., 60 x 60 mm) are placed on a glass cradle and immersed in the solution in such a way that the coupons are evenly exposed. 

Oldfield JW. Test techniques for pitting and crevice corrosion resistance of stainless steels and nickel alloys in chloride containing environments. International Materials Review, 32, 1987 3 153—170. 

ASTM G48-76 (1980) Standard Test Methods for Pitting and Crevice Corrosion Resistance of Stainless Steels and Related Alloys hy Use of Ferric Chloride Solution. 

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