According to the previous investigations of stress corrosion cracking behavior on α/β brass being used as commercial brass, stress corrosion cracking initiates on β phase of brass. However, there are few reports on β brass single crystals.
In order to clarify the stress corrosion cracking mechanism of β brass, stress corrosion cracking tests were performed on Cu-47.3 at % Zn alloy single crystals (β brass) oriented to <411> and <320> in ammoniacal vapor at 298±1K.
In ammoniacal vapor, β brass single crystals were attacked and stress corrosion cracking was observed at a lower stress level than the yield stress. It is very different from the behavior of α brass single crystals.
Corrosion groove was formed along the primary slip trace, that is {110} trace, and propagated along {211} trace at once. A microcrack initiated at the bottom of groove and propagated along {110} trace macroscopically, but the crack propagated in a zigzag way along {211} trace microscopically.
