CHANGES IN GLASS-FORMATION AND GLASS-FORMING ABILITY OF ND2FE14B BY THE ADDITION OF TIC

The glass forming ability (GFA) of a stoichiometric Nd2Fe14B alloy mod ified with TiC additions was studied. Structural, magnetic, and therma l measurements of as-quenched melt-spun ribbons indicate increasing en hancement of GFA with increasing amounts of TiC addition. The limit of the glass formation range and the amount of glass formed at a particu lar cooling rate also increased with TiC addition. Enhanced GFA was co ncurrent with changes in the intrinsic properties of the glass. The cr ystallization temperature, as well as the transformation rate of cryst allization, was raised by TiC addition. The intrinsic magnetic propert ies of the glass were changed with reductions in saturation magnetizat ion and Curie temperature T-c with increasing amounts of TiC addition. The intrinsic glass changes were related to changes in the local shor t range order of the glass and are consistent with a reduction in free volume and an increased packing efficiency. These changes in local st ructure of the glass increase the glass stability, which means that le ss undercooling is needed to prevent crystallization. Thus, at a parti cular cooling rate, a higher percentage of glass will be formed and th e GFA is increased.