The Effect of Environment, Cold Work, and Crystallography on the Stress Corrosion Cracking of C36000 Alloy

Abstract

Abstract Stress Corrosion Cracking (SCC) of C36000 brass, a multiphase copper-zinc alloy, in two ammoniacal environments, aqueous and vapor, was examined. Both environments caused a significant decrease in mechanical properties relative to the values measured in air. The effect of cold working the alloy on SCC was determined. Increasing cold work increased resistance to SCC, as determined by constant load tests in both ammoniacal environments and constant strain rate tests in ammonia vapor. The dependency of cold work on SCC was determined to result from the preferred orientation imparted during cold working. No effect of cold work was found in constant strain rate tests in ammoniacal solution. This is attributed to the lower cupric ion concentration in the solution. The crystallographic dependence of SCC in 70 Cu-30 Zn brass was investigated. It was determined from single crystal studies that SCC initiates along (111) planes.