The development of low-temperature heat-treatable high-pressure die-cast Al–Mg–Fe–Mn alloys with Zn

Abstract

In the present work, a novel low-temperature heat-treatable recycled die-cast Al–Mg alloy was developed by adding Zn into non-heat-treatable Al–5Mg–1.5Fe–0.5Mn alloy. The results showed that Zn additions resulted in the formation of equilibrium phase T-Mg32(Al, Zn)49 under as-cast condition, which can be dissolved into the α-Al matrix at a relatively low solution temperature (430 °C) and thus set the base for the low-temperature heat treatment. The mechanical test results indicated that Zn additions had a smooth liner improvement in the strength of all as-cast alloys and T6-state alloys with 1% and 2% Zn as its concentration increased but resulted in a sharp improvement on the strength of T6-state alloy when Zn concentration increased from 2 to 3%. TEM analysis revealed that the precipitate in T6-state Al–5Mg–1.5Fe–0.5Mn–3Zn alloy is η′ phase, rather than the widely reported T″ or T′ phase in other Al–Mg–Zn alloys with approximately same Mg and Zn concentrations. After the optimized low-temperature T6 heat treatment (solution at 430 °C for 60 min and ageing at 120 °C for 16 h), the Al–5Mg–1.5Fe–0.5Mn–3Zn alloy exhibits the yield strength of 321 MPa, ultimate tensile strength of 445 MPa and elongation of 6.2%.

Boosting for concept design of casting aluminum alloys driven by combining computational thermodynamics and machine learning techniques

“…The strategic workflow for the alloy design approach driven by computational thermodynamics is shown in Figure 2. As demonstrated in the figure, computational thermodynamics based on a reliable thermodynamic database and software/code can provide accurate predictions of different factors determining the castability [81][82][83][84][85][86] , cracking tendency [87][88][89][90] , grain refinement [91][92][93] , microstructure modification [94][95][96][97] , and basic physical properties [98][99][100][101] of casting aluminum alloys, from which the alloy composition [95] , heat treatment mechanisms [102] and even manufacturing means [102] can be optimized, e.g., by using multi-objective design strategy.…”

“…The modification of the eutectic structure is also an important way to improve the mechanical properties of aluminum alloy, and the competitive growth of different eutectic structures is the key to modifying the eutectic structure [94,96,97] . Therefore, to study the competitive growth of multiphase structures, it is necessary to thoroughly analyze the solidification of aluminum alloys.…”

Effect of Zinc and Severe Plastic Deformation on Mechanical Properties of AZ61 Magnesium Alloy

“…In the aerospace, automotive, and green energy industries, the concept of employing large structural components has gained widespread acceptance due to their immense potential in enhancing operational efficiency, reducing carbon dioxide emissions, and achieving light-weighting. The pursuit of these characteristics has driven extensive research and development efforts [1][2][3][4]. Magnesium alloys, being the lightest structural metals, are considered a powerful choice for achieving industrial light-weighting.…”

Investigation of Evolution of Microstructure, Mechanical Properties, and Corrosion Resistance of Novel Al-Mg-Si-Ag Alloy

“…Currently, 5xxx aluminum alloys (Al-Mg based alloys) are widely used in fields such as automobiles and ships due to their low density, high corrosion resistance, high specific strength, and good welding performance [1][2][3]. However, the strength of 5xxx aluminum alloys is greatly limited owing to the non-heat-treatable feature [4][5][6].…”