Estimation of Atmospheric Corrosion of High-Strength, Low- Alloy Steels

This data analysis was undertaken to investigate the weatherability of steels whose compositions do not fall in the range of ASTM Standard G101, Estimating the Atmospheric Corrosion Resistance of Low-Alloy Steels (1). This standard was developed to estimate the corrosion resistance of low-alloy weathering steels from chemical composition data and from actual atmospheric exposure tests. This standard is limited to steels within the composition range outlined in TABLE 1. There are many high-strength, low-alloy steels that are used at the present time or that are under development with chemical composition ranges extending beyond the chemical compositions of steels covered by the ASTM Standard G101. These steels may contain more nickel and more copper or elements not included in the G101 Standard. Ability to estimate the weatherability of these steels is of current interest. The G101 corrosion index, which is used to predict whether a steel is weatherable, is based on the work of Legault and Leckie (2), who utilized part of an extensive database published by Larrabee and Coburn (3). This database (3) contains steels with concentrations of elements shown in TABLE 1. The ten steels with the highest corrosio