冷等静压压力对烧结钕铁硼磁体性能影响的研究

Effect of Cool Isostatic Pressure on Magnetic Properties of sintered Nd-Fe-B Magnet

烧结钕铁硼磁体采用粉末冶金法制备,主要步骤为速凝片(SC)、氢破(HD)、气流磨(JM)、压型、冷等静压(CIP)、烧结。本文主要研究冷等静压对于压坯密度、磁体磁性能和磁体取向度的影响。结果显示,冷等静压压力在170和200MPa时磁体获得较好的剩磁。随着冷等静压压力的增加,磁体裂纹和孔隙度减少。最佳的冷等静压压力可以使磁体在烧结后获得较好的取向度和剩磁的提高。

The sintered Nd-Fe-B magnet were prepared by powder metallurgic method and the principal steps are strip casting, hydrogen decrepitation, jet milling, pressing, cool isostatic pressing(CIP) and sintering. In this manuscript, the effect of cool isostatic pressure on the green-pact density, magnetic properties and alignment coefficient were studied. The results showed that the optimal product Br is 170 and 200 MPa cool isostatic pressure. With the enhancement of cool isostatic pressure the crack and voids were decreased. The optimum cool isostatic pressure will enable magnets to maintain increasing alignment coefficient after sintering process, resulting in the enhancement of Br.