Abstract
It was reported in the previous paper that the resistance to stress corrosion cracking and mechanical properties of Al-Zn-Mg alloys depend upon conditions of heat treatment. The stress corrosion cracking of Al-4.2%Zn-1.4%Mg alloy was tested by cantilever loading system in aqueous solution of 5.3% NaCl+0.3%H2O2.
The results obtained were summarized as follows:
(1) The resistance to stress corrosion cracking was increased, but the mechanical strength was decreased with the decrease of quenching rate.
(2) The resistance to stress corrosion cracking was not always increased with the drop of temperature of solution treatment.
(3) There was not always found any correlation between the resistance to stress corrosion cracking and the width of precipitate-free-zone.
