بررسي ساختار، سختي و خواص كششي آلياژ جديد فوق مستحكم آلومينيم Al-12Zn-3Mg-2/5Cu با بكارگيري عوامل جوانه زاي Al-5Ti-1B و Al-5Zr

Investigation of Structure, Hardness and Tensile Properties of a New Super High Strength Aluminum Alloy Al-12Zn-3Mg-2.5Cu Using Al-5Ti-lB and Al-5Zr Grain Refiners

High strength aluminum alloys (7XXX series), have many applications in the aerospace industries. In order to improve the mechanical properties of these alloys many efforts have been done. These mechanical properties are the functions of many factors like microstructure, chemical composition and processing parameters. In this study the effect of Al-5Ti-lB and Al-5Zr grain refiners on the structural parameters (average grain size and phase morphology), hardness and tensile properties of a new super high strength aluminum alloy (Al-12Zn-3Mg-2.5Cu) was investigated. The results showed that the addition of the grain refiners decreases average grain size of the alloy and increases the hardness and tensile properties. Al-5Ti-lB master alloy, is more effective for the improvement of these properties. Also, by adding A1-5TMB master alloy, the phase morphology has been changed. But Zr has not any effect on the phase morphology.