Dendrite growth morphologies in rapidly solidified Al-4.5wt.%Cu droplets

4th International Conference on Advances in Solidification Processes

材料科学;物理学

Bedel, M.^1 ; Reinhart, G.^1 ; Bogno, A.-A.^2 ; Nguyen-Thi, H.^1 ; Boller, E.^3 ; Gandin, Ch-A^4 ; Henein, H.^2

Aix-Marseille University and CNRS, IM2NP UMR 7334, Campus Saint-Jérôme, Case 142, Marseille Cedex 20

13397, France^1

AMPL, Department of Chemical and Materials Engineering, University of Alberta, Canada^2

ESRF, European Synchrotron, CS 40220, Grenoble Cedex 9

38043, France^3

MINES ParisTech and CNRS, CEMEF UMR 7635, Sophia Antipolis

06904, France^4

关键词: Atomization process;    Controlled process;    Conventional casting;    Crystallographic axes;    Microstructural features;    Microstructure morphologies;    Synchrotron x rays;    Three-dimensional reconstruction;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/117/1/012055/pdf
DOI  :  10.1088/1757-899X/117/1/012055

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

The impulse atomization process developed at the University of Alberta (Canada) enables metallic powders to be solidified with controlled process parameters and improved properties. In order to investigate the microstructure morphologies in droplets of Al- 4.5wt.%Cu alloys, three-dimensional reconstructions of several droplets are obtained by using synchrotron X-ray micro-tomography, allowing a visualization of the inner microstructure in three dimensions. The analysis of the reconstructed volumes reveals that a wide range of morphology, from highly branched to "finger-bundle", can be obtained for different droplets of similar diameter and produced in the same batch. Unexpectedly for this alloy, microstructural features also indicate that the development of the dendrite arms (primary and of higher orders) occurs in most droplets alongcrystallographic axes, instead of the usualdirections observed in conventional casting technologies.