退火Fe_（73．5）Cu_1Nb_3Si_（13．5）B_9合金中α－Fe（S

THE ORDERING OF THE α-Fe(Si)PHASE IN Fe_(73.5)Cu_1Nb_3Si_(13.5)B_9 ANNEALED ALLOY

用ＸＲＤ法研究了退火Ｆｅ７３．５Ｃｕ１Ｎｂ３Ｓｉ１３．５Ｂ９合金中α－Ｆｅ（Ｓｉ）晶化相的有序化过程．结果表明，Ｆｅ７３．５Ｃｕ１Ｎｂ３Ｓｉ１３．５Ｂ９非晶合金在４９０℃，１ｈ退火后，α－Ｆｅ（Ｓｉ）晶化相是具有ＤＯ３结构的有序相，有序畴为球形，直径为７．０ｎｍ，它随退火温度的升高而长大，在５９０℃退火后达１０．９ｎｍ，与α－Ｆｅ（Ｓｉ）的尺寸相当．此时，α－Ｆｅ（Ｓｉ）的有序度为０．８在８５０℃，１ｈ退火后，α－Ｆｅ（Ｓｉ）的ＤＯ３超点阵线条消失．在５５０℃等温退火时，α－Ｆｅ（Ｓｉ）的ＤＯ３有序畴先为椭球状，于６０ｍｉｎ退火后形成球状，直径为１０ｎｍ．

The ordering of the α-Fe(Si) phase in Fe73.5Cu1Nb3Si13.5B9 annealed alloy has been studied by using XRD. Experimental results show that the α-Fe(Si) crystalline phase in Fe73.5Cu1Nb3Si13.5B9 alloy anealed at 490℃, 1h has DO3 superlattice structure, the shape of the DO3 ordering domain is spherical, its diameter is 7.0nm. The size of the ordering domain increases with increasing the annealing temperature.When the annealing temperature is 590℃, the size of the ordering domain of α-Fe(Si) is 10.9nm, which is nearly as large as that of α-Fe(Si) phase at the same time, the degree of order of α-Fe(Si) phase is about 0.8.When Fe73.5Cu1Nb3Si13.5B9 amorphous alloy is annealed at 550℃, first the shape of the DO3 ordering domain of α-Fe(Si) phase is spheroidal, then it becomes spherical when the annealing time is over 60 minutes,and its size is 10nm.