Pj. Mcguiness et al., MAGNETIC-PROPERTIES AND MICROSTRUCTURE IN NDDYFEBZR-HDDR, Journal of magnetism and magnetic materials, 188(1-2), 1998, pp. 119-124
Cast alloys with a range of compositions based on Nd1.5Fe77B8 with add
itions of Dy and Zr were produced by a conventional casting method. Zr
was added prior to casting in the form of either zirconium or zirconi
a. The materials were processed using the hydrogen decrepitation, disp
roportionation, recombination (HDDR) technique in order to develop the
fine microstructures necessary for high coercivities. Magnetic measur
ements on bonded samples produced from the HDDR powders indicated that
additions of Zr tended not to affect the recombination temperatures a
t which the material began to develop high coercivity, but was clearly
observed to extend the temperature range over which high coercivity m
aterial could be produced. Microstructural analysis revealed that the
Zr-doped samples were less prone to the explosive grain growth exhibit
ed by the Zr-free samples at these temperatures. (C) 1998 Elsevier Sci
ence B.V. All rights reserved.