(北京科技大學(xué) 材料科學(xué)與工程學(xué)院，新金屬材料國家重點(diǎn)實(shí)驗(yàn)室，北京 100083)
摘 要: 研究磁粉粒度對注射成形粘結(jié)NdFeB磁體性能的影響。結(jié)果表明：隨著磁粉粒度減小，喂料粘度值升高，粘流指數(shù)n值降低，其注射工藝性能更好；制備粘結(jié)磁體的抗壓強(qiáng)度更高，但其不可逆磁損失也增大。NdFeB磁粉粒度太粗或太細(xì)均不利于磁體性能的提高，其最佳粒徑范圍是80~100 μm；通過粒度級配可以降低喂料粘度值或提高臨界裝載量，在此基礎(chǔ)上制備高性能的各向異性粘結(jié)NdFeB磁體，其Br、iHc、(BH)max及σbb分別為878 mT、1 212.3 kA/m、128 kJ/m3及73 MPa
關(guān)鍵字: 粘結(jié)磁體；釹鐵硼；注射成形；粉末粒度
（State Key Laboratory for Advanced Metals and Materials, School of Materials Science and Engineering,University of Science and Technology Beijing, Beijing 100083, China）
Abstract:The effects of particle size on the properties of injection-molded bonded NdFeB magnet were investigated. The results showed that, as the particle size decreased, the feedstock’ viscosity increased and its fluid exponent decreased, which indicated that the feedstock was more excellent in process properties; the compressive strength of the bonded magnet was improved while the irreversible magnetic flux loss reduced. It was also found that the optimal particle size for injection-molded bonded magnet was 80−100 μm, the particle size smaller or higher than this range resulted in deterioration in properties. By varying the proportions of particles of different sizes, the viscosity of the feedstock decreased or critical powder volume fraction increased. On the basis of these, the injection molding anisotropic bonded NdFeB magnet with the high magnetic properties was obtained, whose remanence Br, intrinsic coercivity iHc, maximum energy product (BH)max and compressive strength σbb are 878 mT, 1 212.3 kA/m, 128 kJ/m3 and 73 MPa respectively
Key words: bonded magnet; NdFeB; injection molding; particle size
