Chemical short-range order domain in bulk amorphous alloy and the prediction of glass forming ability  

作　　者：惠希东 姚可夫 寇宏超 陈国良 

机构地区：[1]State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China [2]Mechanical Department, Tsinghua University, Beijing 100084, China

出　　处：《Science China(Technological Sciences)》2003年第6期581-592,共12页中国科学（技术科学英文版）

基　　金：This work was supported by the National Natural Science Foundation of China(Grant Nos.59871025 and 50171006);the Hi-tech Research and Development Program of China(Grant No.2001AA331010);the NationalMajor Basic Research Project of China(973)‘Scientific Foundation of Advanced Preparation,Forming and Processing for Materials’(Grant No.G2000 67201-3,);the Major Program of Science and Technology of Beijing(Grant No.H020420030320).

摘　　要：Short-range order domains of face central cubic Zr2Ni (F-Zr2Ni) and tetragonal Zr2Ni (T-Zr2Ni) type structure with a size about 1–3 nanometers were observed in bulk amorphous Zr52.5Cu17.9Ni14.6Al10Ti5 alloy by using HREM and nano-beam electron diffraction technique. A new thermodynamic model was formulated based on the concept of chemical short-range order (SCRO). The molar fractions of CSRO and thermodynamic properties in Ni?Zr, Cu?Zr, Al?Zr, Al?Ni, Zr?Ni?Al and Zr?Ni?Cu were calculated. According to the principle of maximum ΔG CSRO, the optimum glass forming ability (GFA) compositions were predicted in binary and ternary alloys. These results were proved to be valid by the experimental data of crystallizing activation energy, ΔT x and XRD patterns. The TTT curves of Zr?Ni?Cu alloys calculated based on CSRO model shows that the lowest critical cooling rate GFA is in the order of 100 K/s, which is close to the practical cooling rate for the preparation of Zr-based BMG alloys.

关 键 词：bulk metallic glasses  CHEMICAL SHORT-RANGE order domain  glass forming ability  THERMODYNAMIC model. 

分 类 号：TQ171[化学工程—玻璃工业]