Formation, microstructure and mechanical properties of Al-Fe base quasicrystalline alloys

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Structural materials : properties, microstructure and processing, 1999-09, Vol.294-296, p.168-172
• Main Authors: Kimura, H M, Sasamori, K, Inoue, A
• Format: Article
• Language: English
• ISSN: 0921-5093

An icosahedral (I) phase in coexistence with Al-phase was formed in the size fraction range up to 125 mu m of atomized Al sub 93 Fe sub 3 Cr sub 2 Ti sub 2 powder. The decomposition temperature of the I-phase is about 790 K. As per energy dispersive X-ray spectroscopy analysis, the constituent composition of the I-phase is l sub 84.2 Fe sub 7.0 Cr sub 6.3 Ti sub 2.5 . It is found that the Al sub 84.2 Fe sub 7.0 Cr sub 6.3 Ti sub 2.5 alloy forms a mostly single I-phase in the melt-spun state. Bulk I-alloys in a rod form were produced by extrusion of the atomized powders at 673 K and an extrusion ratio of 10. The extruded Al93Fe3Cr2Ti2 alloys have good mechanical properties, i.e., sigma sub 0.2 of 550 MPa, sigma sub uts of 660 MPa and epsilon sub p of 4.5% at room temperature and sigma sub 0.2 of 330 MPa, sigma sub uts of 350 MPa and sigma sub p of 1.5% at 573 K. The I-based Al sub 93 Fe sub 3 Cr sub 2 Ti sub 2 alloy is expected to be useful as a new type of high-elevated temperature strength material.