Consolidation of Al-Fe-Nd Atomised Powders

摘要

Aluminium based alloys with a nanocomposite microstructure consisting of a dispersion of Al particles in nanoscale size in an amorphous matrix can be produced by rapid solidification processes. Such microstructures are of interest since they can present high tensile strength without loss of ductility. A novel alloy powder of the Al-Fe-Nd system was developed, and produced by gas atomisation. The atomised powder showed a high level of metastability, Presenting in the finer powder range a nanocomposite microstructure composed of amorphous phase and nanocrystals. In the present work, powders of different size ranges obtained by helium atomisation of an Al_90Fe_5Nd_5 alloy, were consolidated. The microstructure of the bulk maerial obtained by hot-extrusion was investigated by X-ray diffraction and scanning electron microscopy. Yield strength above 700 MPa was obtained by the hot extrusion of atomised powders smaller than 25 μm.