PHILOSOPHICAL MAGAZINE LETTERS, vol.92, no.7, pp.314-326, 2012 (SCI-Expanded)
The microhardness and microstructural characteristics and subsequent heat treatment of conventionally solidified Al64Cu20Fe12Si4 quasicrystal were investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM) together with energy dispersive spectroscopy (EDS), differential thermal analysis (DTA), and Vickers microhardness tester. XRD analysis indicated that the conventionally solidified samples showed a quasicrystalline icosahedral phase (i-phase) together with cubic beta-AlFe, tetragonal theta-Al2Cu, and monoclinic lambda-A(13)Fe(4) crystal phases. However, the i-phase together with cubic beta-AlFe and monoclinic lambda-A(13)Fe(4) phases observed heat threaded samples. As-cast and subsequently heat-treated quasicrystal samples were measured using a microhardness test device. Vickers microindentation tests were carried out on the heat-treated quasicrystal samples with the load ranging from 1 to 500 mN at room temperature. The melting point of the i-phase was determined as 900 degrees C by DTA examinations.