Semi-solid die casting technology refers to the aluminum alloy in the process of solidification from liquid to solid, when the temperature drops to the liquidus and solid phase line (solid-liquid two-phase zone), by applying a certain external influence, the microstructure of aluminum alloy is a liquid phase surrounded by spherical solid phase organization, in this temperature range, aluminum alloy can be like a solid with a certain fixed shape. It can also flow easily after being squeezed by a slight external force, and the process of die-casting aluminum alloy in this state is used.
The technology was originally created in the United States in the 1970s, and has been recognized by the industry in developed countries. The semi-solid technology of Yuefeng Technology Co., Ltd. is currently in the international advanced and domestic leading level.
Semi-solid die casting technology breaks the traditional dendrite solidification mode, and has unique advantages in composition and structure uniformity, improving the comprehensive mechanical properties of formed parts and reducing internal defects. Its die casting temperature is lower than that of ordinary liquid die casting, solidification shrinkage leads to less (or no) casting porosity, stable filling leads to less (or no) porosity defects and oxide inclusions, and T6 heat treatment and subsequent welding can be carried out to improve the casting quality problems existing in traditional casting methods.
The lower forming temperature of the semi-solid makes the thermal impact of the mold small and prolongs the life of the mold. Compared with forging and other hot deformation forming process, semi-solid forming deformation resistance is small, so that a large deformation can be processed to form complex shapes and parts with high precision and performance requirements, to overcome the shortcomings of high cost in traditional forging, can not form complex parts, with net forming, high quality, high performance, low energy consumption, low cost and many other unique advantages. It is praised by domestic and foreign researchers as one of the most promising metal processing technologies in the 21st century.
The microstructure of conventional die casting is bifurcated. The microstructure of semi-solid die casting is nearly spherical and relatively dense, which solves the problem of non-heat treatment and non-welding in conventional die casting.
