Morphological and microstructural characterization of Al95Fe2 Cr2 Ti1 powders produced by two different gas atomizers

Abstract

This work aimed to produce powders of Al95Fe2Cr2Ti1 quasicrystalline phase former alloy using different atomizers, Hermiga (PH) and Spray forming/gas atomizer (PS), and investigate the powder characteristics as morphology, size distribution, flowability, microstructure, phase formation and thermal stability. The atomized powders were separated in different particles size ranges: <32μm, 32-45 μm and 45-75 μm. The characterization of powder microstructure and morphology for each range was carried out by X-ray diffraction, Optical and Scanning Electron Microscopy, Differential Scanning Calorimetry (DSC) and semi-quantitative composition analysis by Energy Dispersive Spectrometer (EDS). The flowability was measured by Carney funnel. The PH powder presented a bimodal particle size distribution and its particles displayed a constant circularity and aspect ratio with microstructure rich in quasicrystalline phase. The PS powder showed a unimodal particle size distribution and the circularity and aspect ratio decrease with increasing particles size. The PS powder flowability was 1.6 times better than PH powder.