摘要
探讨了铸态Ti-Zr-Ni准晶的成分偏析问题。通过水冷铜模吸铸法制备6个名义成分为Ti40Zr40Ni20的φ3mm圆柱状样品,采用X射线衍射与能谱分析分别对样品底端和顶端的相结构与成分分布进行了测定。结果表明,这些样品在一定长度范围内都形成了近单一的二十面体准晶相,最长的准晶样品达到40mm。它们都存在明显的宏观成分偏析,其中Ni易于在样品的底端富集,而Ti在顶端富集,这属于比重偏析;而Zr的偏析与工艺控制有关,可通过改善工艺消除它。
Composition segregation of as-cast Ti-Zr-Ni quasicrystal (QC) is investigated initially. Six rods with the same nominal composition Ti40Zr40Ni20 (at. %) and 3 mm in diameter, were manufactured by using water-cooled copper mold suction-casting method, and then analyzed by XRD,SEM and EDS. The results indicate that almost icosahedral quasicrystals were formed in a certain length, the longest quasicrystal sample can reach up to 40 mm. There is obvious segregation on these samples. Due to different density, Ni is liable to enrich on the bottom of the rods, while Ti gather on the top. And the segregation of Zr resulting from imperfect technical control during the sample preparation could be eliminated by improving technology.
出处
《铸造技术》
CAS
北大核心
2007年第11期1494-1497,共4页
Foundry Technology