Study on the effect of aging heat treatment temperature on the microstructure and properties of soluble Al-Zn-Mg-Ga-In-Sn aluminum alloys in solid solution state

Abstract

This study aimed to develop a soluble aluminum alloy material for isolation tools, characterized by high hardness, high tensile strength, and low dissolution rate. To achieve this, the Al-Zn-Mg-Ga-In-Sn soluble aluminum alloy was cast at high temperatures using a medium frequency metal induction melting furnace. The effects of different aging heat treatment processes on the mechanical properties and dissolution performance of the Al-Zn-Mg-Ga-In-Sn soluble aluminum alloy, which had undergone a solution heat treatment at 470℃ for 12 hours followed by air cooling to 25℃, were investigated. The results indicated that after aging heat treatment at 175℃ for 2 hours followed by air cooling to 25℃, the alloy exhibited uniform grain size, averaging 35±2μm. The precipitated phase Mg2Sn had an average size of 7.6±1.0 μm, with fewer in number, primarily located at the grain boundaries. Furthermore, the alloy demonstrated excellent mechanical properties, including a tensile strength of 334±1 MPa, yield strength of 226±1 MPa, and elongation of 16.6±0.5 %. Additionally, its hardness reached 91±3 HB. The dissolution rate in 90℃ distilled water was 1.6±1.0 g·h−1·cm−2, with the alloy surface showing relatively uniform dissolution characteristics during the process, and a dissolution depth of 741±5 μm.