grain size;;nucleation

关键词:Pr-Fe-B magnet;;coercivity;;grain size;;nucleation;;cast-hot press
摘要:<正> Characteristics of magnetic hardening in cast-hot pressed magnet Pr_(19)Fe_(74.5)B_5Cu_(1.5)were stu-died.The neodymium price
http://www.999magnet.com/products/142-neodymium-price microstructure features and virgin magnetization curve reveal a nucleation control-led coercivity mechanism.Regression analysis shows that the intrinsic coercivity variesinversely as the logarithm of the average grain size:_iH_c(MA/m)=1.7312-0.48161nd(μm)which confirms the randomness of nucleation of reversed domains and the statistical nature ofcoercivity,indicating that the decrease of grain size would reduce the average number of de-fects on its surface and lower the probability of magnetization reversal of a grain and the cu-mulative fraction of the grains that have reversed their magnetization.Coercivity is thus en-hanced.