Rapidly solidified Ag-Cu eutectics: A comparative study using drop-tube and melt fluxing techniques

4th International Conference on Advances in Solidification Processes

材料科学;物理学

Yu, Y.^1 ; Mullis, A.M.^1 ; Cochrane, R.F.^1

Institute for Materials Research, University of Leeds, Leeds

LS2 9JT, United Kingdom^1

关键词: Anomalous eutectic;    Comparative studies;    Computational model;    Drop tube technique;    Eutectic alloys;    Lamellar eutectic;    Melt-fluxing technique;    Rapidly solidified;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/117/1/012053/pdf
DOI  :  10.1088/1757-899X/117/1/012053

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

A comparative study of rapid solidification of Ag-Cu eutectic alloy processed via melt fluxing and drop-tube techniques is presented. A computational model is used to estimate the cooling rate and undercooling of the free fall droplets as this cannot be determined directly. SEM micrographs show that both materials consist of lamellar and anomalous eutectic structures. However, below the critical undercooling the morphologies of each are different in respect of the distribution and volume of anomalous eutectic. The anomalous eutectic in flux- undercooled samples preferentially forms at cell boundaries around the lamellar eutectic in the cell body. In drop-tube processed samples it tends to distribute randomly inside the droplets and at much smaller volume fractions. That the formation of the anomalous eutectic can, at least in part, be suppressed in the drop-tube is strongly suggestive that the formation of anomalous eutectic occurs via remelting process, which is suppressed by rapid cooling during solidification.