Structures and macrosegregation of a 2024 aluminum alloy fabricated by direct chill casting with double cooling field

Abstract

Large-size aluminum alloy ingots produced by traditional direct chill (DC) casting, especially the 2xxx and 7xxx series, often have defects such as inhomogeneous structure, macrosegregation, and hot cracks [1][2][3][4] . Although adding grain refiners improves the quality of largesize ingots, it could lead to agglomeration of nucleating particles and fading effect [5][6] . In addition, physical methods, including mechanical stirring [7][8] , ultrasonic vibration [9] , and electromagnetic stirring [10] , are not easy to apply in the DC casting process because of the expensive and specific equipment requirements.Recently, several new methods have been developed by adding intercooling in the DC casting process. For instance, an in-mold cooler with a cooling end made of highly pure graphite can be inserted into the melt to absorb and transfer the heat during the liquid or gas flow in the cooler [11][12] . Another way to enhance

The Effect of Extrusion and Heat Treatment on the Microstructure and Tensile Properties of 2024 Aluminum Alloy

“…For the as-cast 2024 aluminum alloy, there were large size grains, serious macroscopic segregation, and coarse eutectic structures at the grain boundary, which resulted in the degradation of mechanical properties. Therefore, given the defects existing in the casting process of 2024, the performance of the 2024 aluminum alloy is eager to be improved by regulating the alloy composition, plastic deformation, homogenization treatment, solution aging treatment, and other means [ 10 , 11 , 12 ]. In recent years, the study of 2024 aluminum alloy mainly focuses on the effect of plastic deformation and heat treatment on the microstructure and properties of the alloy.…”

Effects of mechanical vibration on filling and solidification behavior, microstructure and performance of Al/Mg bimetal by lost foam compound casting

“…Aluminum alloy (Al alloy) and magnesium alloy (Mg alloy) are important engineering light metals, and each of them has its own advantages and disadvantages [1][2][3][4][5] . Al/Mg bimetal combines the advantages of the Al alloy and Mg alloy and has good comprehensive performance, therefore having broad application prospects in the weapons, automobile, aviation, aerospace, electronic 3C, etc [6][7][8] .…”