EFFECT OF MOLYBDENUM SUBSTITUTION ON B2 ANTIPHASE DOMAIN FORMATION IN RAPIDLY SOLIDIFIED FE-AL-MO ALLOYS

Studies at Sheffield have shown that the increase in B2 ordering temperature obtained with increase in aluminium content in rapidly solidified Fe-Al-X (X = Cr, Mo) alloys results in an increase in B2 antiphase domain (APD) size. The present contribution concerns the effect of increasing molybdenum substitution for iron in such systems, which is shown to increase the ordering temperature but decrease the B2 APD size. The results are discussed in terms of the extension of solid solubility of molybdenum by rapid solidification, molybdenum segregation to the antiphase boundaries, and molybdenum diffusion in these alloys.