Construction of Tb-rich shells via novel interdiffusion approach to tackle coercivity-remanence trade-off
Source abstract
Abstract
The strategic introduction and efficient utilization of heavy rare earth elements within Nd-Fe-B-based permanent magnets are instrumental in achieving an optimal balance between remanence ( B r) and high coercivity ( H cj). Herein, we propose a novel interdiffusion approach based on hydrogen decrepitation (HD) for the cost-effective and high-performance sintered Nd-Fe-B magnets. With the aim of generating continuous Tb-rich shells on the grain surface, which favors high B r and high H cj, strip cast (SC) flakes homogeneously mixed with 0.9 wt% Tb were processed by the HD. It is shown that the formation of (Nd, Tb)-Fe-B by the interdiffusion of Nd-Fe-B and Tb during de-hydrogenation, as well as the interdiffusion of Nd-Fe-B and (Nd, Tb)-Fe-B during sintering and tempering, is the key to the construction of Tb-rich shells. As a result, a magnet (Mag-Tb&HD) with maximum magnetic energy product (( BH) max) of 52.21 MGOe was achieved, which is superior to magnet prepared form SC flakes containing 0.9 wt% Tb (Mag-Tb&SC, ( BH) max=49.36 MGOe) and the magnet prepared by adding 0.9 wt% Tb to the jet milling (Mag-Tb&JM, ( BH) max=50.41 MGOe).
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Research context
OpenAlex topics: Magnesium Alloys: Properties and Applications · Magnetic Properties of Alloys · Aluminum Alloys Composites Properties
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
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