A study of magnetic properties and structure of magnets of type (Nd, Pr) – (Tb, Dy, Gd) – (Fe, Co, Al, Cu, Re) – B after heat treatment
Properties of magnets of type (Nd, Pr, R)2(Fe, Co, M)14B are studied in a wide temperature range after different variants of heat treatment. The inflections on the demagnetization curves are associated with defects on the surface of the small-size test pieces. An additional inflection on the demagnetization curve at 10 – 20 K is associated with the presence of a R1.1(Fe, Co)4B4 ferromagnetic phase in the studied temperature range.
Key wordsmagnet induction coercive force heat treatment structure
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