The effects of erbium addition on the rheological properties and microstructure of a semisolid A356 alloy were studied. The semisolid slurries were prepared through the serpentine channel technique before they were thixoformed using parallel-plate compression with cylindrical discs. The grain and globule size decreases as the Er content increases, resulting in an improved and uniform distribution of spherical primary α-Al phase within the semisolid slurry. The addition of the Er modifies the grain morphology and size of the α-Al grains, resulting in a better and more uniform distribution of spherical primary α-Al phase within the semisolid slurry. As a result, rheocast quality index increases with the addition of Er, which is suitable for the thixoforming process. The A356 alloy without Er has the highest viscosity herein. The viscosity decreases, and the flow characteristics of the semisolid feedstock are expected to improve when Er is added as a result of the refinement of primary α-Al and modification of eutectic silicon. Furthermore, the refined semisolid A356 alloys with Er show a slightly larger fraction of high-angle grain boundaries compared to that for the unrefined alloy.

研究了添加铒对半固态 A356 合金流变性能和显微组织的影响。半固体浆料通过蛇形通道技术制备，然后使用圆柱形圆盘平行板压缩进行触变成型。随着 Er 含量的增加，晶粒和小球的尺寸减小，导致球形初级 α-Al 相在半固体浆料中的分布得到改善和均匀分布。Er的添加改变了α-Al晶粒的晶粒形态和尺寸，导致球形初生α-Al相在半固态浆料中的分布更好、更均匀。结果，流变铸件质量指数随着 Er 的添加而增加，适合触变成型工艺。不含 Er 的 A356 合金在此粘度最高。粘度降低，由于初级α-Al的细化和共晶硅的改性，当添加Er时，半固态原料的流动特性有望得到改善。此外，与未精炼合金相比，含 Er 的精炼半固态 A356 合金的高角晶界比例略大。