DEFECT AND ATOMIC ORDERING STUDIES IN HIGHLY DEFORMED AND DISORDERED Fe_72Al_28 ALLOY

摘要

The results of positron annihilation and Mossbauer spectroscopies in Fe_72Al_28 alloy with different structural morphology obtained by sever deformation and by quenching from a high temperature are presented. The changes in atomic ordering and in defect arrangements after recovery and ordering annealing in both highly deformed and highly disordered samples are also pursued and discussed. It is shown that the dominant component of 184 ps in the positron lifetime spectrum of a highly disordered Sample corresponds to the annihilation in vacancies which prefer to occupy that sublattice in Do_3 Superstructure containing both aluminium and iron atoms.