Microstructure and temperature dependent of coercivity of hot-deformed Nd–Fe–B magnets diffusion processed with Pr–Cu alloy
Source abstract
Abstract
Abstract The coercivity of hot-deformed Nd–Fe–B magnet was substantially enhanced from 1.0 T to 2.6 T by the grain boundary diffusion process using Pr–Cu alloy. However, the temperature dependence of coercivity is larger compared to the sample diffusion processed with Nd–Cu. Microstructure studies showed a good isolation of platelet shaped Nd 2 Fe 14 B grains by Pr-rich intergranular phase, which explains pronounced coercivity at room temperature. Small portions of Nd 2 Fe 14 B become (Nd,Pr) 2 Fe 14 B phase, which has a higher anisotropy field compared to that of the Nd 2 Fe 14 B phase at room temperature, while it becomes lower than that of the Nd 2 Fe 14 B phase above ∼110 °C. Co is depleted from the (Nd,Pr) 2 Fe 14 B phase, which is considered to cause a slight decrease in Curie temperature. Micromagnetic simulations with the magnetically isolated grains including (Nd,Pr) 2 Fe 14 B regions showed that the degradation of thermal stability of coercivity in the Pr–Cu diffusion processed sample is due to the large temperature dependence of anisotropy field in the (Nd,Pr) 2 Fe 14 B regions.
Source: openaire · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Magnetic Properties of Alloys · Magnetic properties of thin films · Magnetic Properties and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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