The application of advances in quench factor analysis property prediction to the heat treatment of 7010 aluminium alloy

Abstract

7010 is an Al–Zn–Mg–Cu forging and plate alloy, primarily used in the aerospace industry for the production of key structural components. These alloys develop their strength through the development of a precipitation-hardened microstructure produced by ageing of a quenched super-saturated solid solution.For over 30 years Evancho and Staley developed quench factor analysis model has been applied successfully to the prediction of post-quenched physical properties, in aged aluminium alloys. In recent years improvements have been made to the initial model incorporating the effect of remaining solute on nucleation rate as a function of temperature. This extends the usefulness of the quench factor approach to beyond the 15% loss in properties, allowing the prediction of properties in both fast-quenched and slow-cooled conditions such as in annealing. Tensile time–temperature–property (TTP) or ‘C’ curves produced by an interrupted quench technique are presented for 7010-T76 including quench factor analysis and subsequent modifications based on an improved non-isokinetic model.