Toles strong alloy did zn-cu-mg low internal stresses

The invention relates to a thick sheet manufacturing process type alloy Al-Zn-Cu-Mg comprising between 4 and 12% zinc, less than 4% magnesium and less than 4% copper, minor elements <= 0 , 5% each, the balance aluminum, said method comprising hot rolling, solution treatment, quenching, controlled stretching with a 0.5% higher proof stress, as well as aging, characterized in that time delay D between the end of the quenching and the start of controlled stretching is less than 2 hours.