IDENTIFICATION OF METASTABLE PHASES IN STRIP-CAST AND SPRAY-CAST AL-FE-V-SI ALLOYS

Second phases have been investigated in the strip-cast and/or spray-ca st Al-Fe-V-Si alloy, and found to be classified into three different t ypes, e.g. icosahedral phase, newly found hexagonal phase, and bce alp ha-AlFeSi. Convergent Beam Electron Diffraction (CBED) analysis shows that the space group of the hexagonal phase is P6/mmm and the lattice parameter of the phase is a=2.514 and c=1.257 nm of which cia ratio is 0.5. Crystallographic orientation relationships among the phases were determined by electron diffraction. All the phases have similar atomi c arrangements, which are constructed by (Fe + V) and (Al + Si) icosah edra, and thereby providing close orientation relationships among them .