Internal friction peak associated with the ordering process in B2 FeAl alloys

The internal friction behaviors of B2 FeAl alloys were examined to understand the correlation between the ordering and the movement of the atomic defects. A new internal friction peak was found at around 540 °C and 570 °C in the oil-quenched Fe57Al43 and Fe47Al53 alloys, respectively, while in the furnace-cooled specimens, the peak disappeared. The peak has the typical phase transition characters, and it is suggested that the peak probably originates from the elevation of the degree of order, which is caused by the jump of antisite atoms to their own sublattice sites by means of the nearest neighboring vacancies. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)