MICROSTRUCTURE AND MAGNETIC-PROPERTIES OF AMORPHOUS AND NANOCRYSTALLINE FE80M7B12CU1 (M = NB, TI OR MO) ALLOYS

The structural and magnetic properties of melt-spun Fe80M7B12Cu1 alloy s (M = Nb, Ti or Mo) were examined in the amorphous as-quenched state as well as after annealing which results in a relaxed amorphous state or a nanocrystalline structure. For samples with M = Mo heat treated a t temperatures below the crystallization onset, a relaxation effect co nnected with a decrease of the Curie temperature of the amorphous phas e from T-c = 265 to 250 K was observed. As expected, annealing of thes e samples at higher temperatures, T-a > 410 degrees C, results in an i ncrease of T-c due to the crystallization of BCC Fe connected with a c hange in the composition of the residual amorphous matrix. The coerciv ity of the Fe80M7B12Cu1 alloys shows a maximum with respect to the ann ealing temperature. (C) 1998 Elsevier Science B.V. All rights reserved .