Effects of solution heat treatment and age hardening on the microstructures and mechanical properties of rheocasting 7075 Al alloy produced by a novel technique, Gas Induced Semi-Solid (GISS) technique, were studied. This work reveals that the optimum solution heat treatment condition for the non-dendritic structured 7075 aluminium alloy was 450 °C for 4 h. Age hardening was performed at temperatures of 120 °C, 145 °C, 165 °C, and 185 °C under various time durations. The peak aging condition was the artificial aging at 120 °C for 72 h, at which a highest tensile strength of 486 MPa with 2% elongation was recorded. This higher strength was caused by higher number density and finer precipitate size of η / phase than other aging temperatures. The main hardening phase was identified to be the η / phase while early nucleation of η phase in the higher aging temperature specimens resulted in lower strengths of the alloy. The activation energy for the precipitate hardening process of the alloy derived in this research was 95,827 J/mol.

T6 heat treatment of rheocasting 7075 Al alloy

Effects of multiple-step thermal ageing treatment on the hardness characteristics of A356.0-type Al–Si–Mg alloy

The microstructure, hardness and tensile properties of a new super high strength aluminum alloy with Zr addition

Effects of Al-5Ti-1B and Al-5Zr master alloys on the structure, hardness and tensile properties of a highly alloyed aluminum alloy

Multistage-aging process effect on formation of GP zones and mechanical properties in Al–Zn–Mg–Cu alloy

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ji-wu Huang

Papers

Single-aging characteristics of 7055 aluminum alloy