The effect of Cu~2+ concentration on the stress corrosion cracking susceptibility of α-brass in cupric nitrate solutions

摘要

The stress corrosion cracking (SCC) susceptibility of α-brass in aqueous cupric nitrate solutions was studied. The effect of the Cu~2+ ion concentration on the stress corrosion crack propagation rte (CPR) was measured. A linear relationship between the logarithm of the CPR and the logarithm of the Cu~2+ concentration was found in all the alloys studied. The slope of this relationship was very close to that reported for the cuprous ion exchange current density and the cupric ion concentration: δlog I_0(C+→Cu)/δ log [Cu~2+]. All the cracks found were treansgranular, and the crack propagation mechanism was explained through the surface mobility SCC mechanism.