ASTM G157-98(2005)

This guide is intended to provide a series of evaluations that will assist engineers dealing with chemical environments in selecting appropriate alloys (1-3). In chemical environments, an important issue for determining general corrosion resistance is the temperature at which an alloy transitions from corrosion at a low rate to corrosion at a much higher rate. Other important concerns include the tendency towards crevice corrosion and stress corrosion cracking resistance, especially in hot chloride-containing aqueous environments.

This guide is also intended for alloy developers to assist them in choosing environments and test methods that are of particular interest to the chemical process industries.

The use of this approach will allow direct comparisons to be made among alloys from various suppliers and, thereby, to assist engineers in selecting the most appropriate materials for further testing to determine suitability in their application.

1.1 This guide covers an evaluation approach that is designed to provide information on the corrosion properties of wrought iron- and nickel-based alloys for the chemical process industries. This guide incorporates test conditions for general corrosion measurements in a variety of environments, crevice corrosion resistance in chloride environments, and stress corrosion cracking resistance in chloride environments.

1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are for information only.

This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and to determine the applicability of regulatory limitations prior to use.