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采用模压设备制备了NdFeB粘结磁体,并研究了粘结助剂(粘结剂和偶联剂)对快淬NdFeB粘结磁体力学性能,包括密度和抗压强度以及磁性能的影响.研究结果表明,添加偶联剂可以提高粘结磁体的性能.使用E-51环氧树脂粘结剂所获得的磁体密度、剩磁、矫顽力、最大磁能积以及抗压强度比用E-44粘结剂的磁体性能要高.随着粘结剂含量的增加,磁体的密度在逐渐降低,磁体的抗压强度在不断变大.而剩磁随着粘结剂含量的增加在不断下降.对矫顽力这个性能来说,1.5%的粘结剂含量为最佳用量. 相似文献
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粘结剂含量对粘结NdFeB磁体磁性能和抗压强度的影响 总被引:2,自引:0,他引:2
用环氧树脂粘结剂制备了NdFeB粘结磁体,探讨了粘结剂含量对粘结磁体磁性能和抗压强度的影响规律及机理.当粘结剂含量为1%(质量分数,下同)时,磁粉不能完全被包覆、粘结,磁体密度、磁性能和抗压强度低;当粘结剂含量为5%时,粘结剂体积分数大,稀释了磁体的磁性能,多余的粘结剂也使磁体抗压强度降低.粘结剂含量为2.5%时磁体具有较佳的性能:剩磁Br=0.616T;内禀矫顽力Hcj=784kA/m;最大磁能积(BH)m=58kJ/m3;抗压强度为236MPa. 相似文献
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研究了一种聚合物粘结SmCo_5磁体和两种不同性能等级的环氧树脂粘结2∶17型稀土-钴磁体开路剩磁和退磁曲线随温度、保温时间和磁体退磁系数的变化。表明三种磁体开路剩磁随温度的可逆变化曲线之间没有大的差异。在75、100和125℃的时效过程中,沉淀硬化型磁体显示出比1∶5型磁体好的磁性稳定性,磁体的退磁系数越大,其开路剩磁不可逆损失也越大。在上述三种温度时效大约5000小时之后,1∶5型磁体的退磁曲线形状产生了较显著的变化。即使在75℃时效5131小时后,B/H=-2的1∶5型磁体的开路剩磁不可逆损失也高达28.5%,而尺寸相同的2∶17型磁体的开路剩磁不可逆损失却只有4.5~8.2%。 相似文献
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注射成形钕铁硼粘结磁体研究的现状及前景 总被引:1,自引:0,他引:1
论述了注射成形钕铁硼粘结磁体的特点及发展趋势,分析了其生产工艺中的4个关键因素,包括磁粉、粘结剂与藕联剂、注射过程、充磁过程,并对这4个关键因素的研究状况作了综合评述,认为今后注射成形钕铁硼粘结磁体的研究开发将主要集中在以下4个方面研究:各向异性粉末和各向异性粘结磁体,研发合适的粘结体系及注射成形工艺参数,开发磁能积更高的磁体,开发耐热钕铁硼粘结磁体。 相似文献
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研究了d-HDDR各向异性NdFeB粘结磁体温压成形过程中粘结剂、润滑剂、成形压力对磁体磁性能的影响.通过温压机理的分析,发现温压工艺的温度主要决定于粘结剂体系的黏度、软化点和凝胶时间.添加适量的润滑剂,可减小粉末间及粉末与模壁间的摩擦力,有利于提高磁体的取向度.增加成形压力能明显提高磁体的密度,从而改善磁体的磁性能.采用合适的温压工艺,可获得取向度高(94%)、磁性能优异[BHmax=159.96 kJ/m3(20.17 MG-Oe)]的粘结钕铁硼永磁体. 相似文献
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通过2种途径将熔体快淬法制得的FeCuNbSiB非晶薄带制成环状粘结磁体。一是将非晶薄带进行晶化处理,再将晶化后的薄带粉碎成不同粒度的粉末,然后与粘结剂相混合制成粘结磁体。二是将非晶薄带直接粉碎成不同粒度的粉末,再将此粉末进行晶化处理,将晶化后的磁粉与粘结剂相混合制成粘结磁体。分析了磁粉粒度和模压压力对粘结磁体性能的影响。并对两种粘结磁体的性能进行比较。结果表明,第一种方法制备的粘结磁体的性能优于第二种。 相似文献
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为了制备出高性价比的粘结NdFeB注射磁体,本文系统的研究了粘结剂、添加剂的含罱以及磁粉装载量对注射磁体的加工性能、磁性能等的影响规律,并从微观上揭示了其机理。本文采用低成本的陶广:快淬钕铁硼磁粉和国产尼龙6粘结剂制备出了磁性能Br为0.5158T、Heb为321kA/m、Hcj为730kA/m和(BH)max为40kl/m^3的注射磁体,其性能与日本Mate公司的RNI-50产品性能相当,而价格却低得多. 相似文献
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The design and measuring potential of the latest generation of the magnetic scanner called Magscanner-Maglab System (MMS) was presented. It enabled the fast acquisition of 3D signals from magnetic sensors and their visualization as digitalized mag- netic images. This system was used for monitoring of a thermal demagnetization process of permanent magnets. The original method and measurement devices were capable for examination of magnetic, mechanical and thermal defects in cylindrical rods made of NdFeB and non-rare earth components. Effectiveness of the method and device was tested for the reference demagnetized magnet dedicated for magnetostrictive actuators. 相似文献
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A three-dimentional finite element micromagnetic algorithm was developed to study the magnetization reversal of Pr2Fe14B single-phase nanocrystalline permanent magnets. A single-phase nanocrystalline Pr2Fe14B magnets composed of 216 irregular shaped grains was built. The magnetic hysteresis loops were simulated by micromagnetic finite element method. The contribution of intergrain exchange coupling ment degree (IGEC) to remanence enhancement is considered related to the alignin oriented magnets, and decreased with improved grain alignment. For the magnets with perfectly crystallo- graphic alignment of grains, the contribution of IGEC to remanence enhancement is nearly zero. The shape of demagnetization curve is not only dependent on grain alignment degree but also on the strength of IGEC in magnets. 相似文献
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从设备改造,技术参数优化,工艺流程变更及新设备新工艺的应用等几个方面阐述了庙沟铁矿提高铁精矿品位的生产实践过程。 相似文献
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通过对高速涡流探伤机组交直流复合退磁系统的合理改进,解决了由于场地局限、厚壁钢管以及新型合金材料带来的剩磁较难退清的问题. 相似文献
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Magnetic field stability of PrFeB magnets developed by GBD for cryogenic permanent magnet undulators
The magnetic field stability of the PrFeB magnets is one of the key points which affect its application in such devices as cryogenic permanent magnet undulators. In this study, the magnetic properties and microstructure of PrFeB magnets, which were developed by the grain boundary diffusion, were examined. The demagnetizing field distribution of the cryogenic permanent magnet undulator made using the PrFeB magnets was simulated by Radia, and the change mechanism of the irreversible demagnetization following treatments at high temperatures was experimentally studied. The results show that the intrinsic coercivity of the PrFeB magnets can be increased by diffusion of Tb. Meanwhile, the remanence of the magnets displays almost no loss, and the increasing range is closely related to the orientation thickness of the PrFeB magnet. Therefore, the PrFeB magnets developed using grain boundary diffusion are found to have extremely high comprehensive magnetic properties. The irreversible demagnetization of the PrFeB magnets developed by grain boundary diffusion for the CPMU is determined to be significantly improved following high-temperature treatments. 相似文献
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《中国稀土学报(英文版)》2019,37(6):628-632
Individual grains with diverse dimensional parameters were introduced to investigate the magnetization reversals in anisotropic Nd2 Fe_(14)B magnets. The micromagnetic simulations were carried out via Object Oriented MicroMagnetic Framework(OOMMF). With the same bottom area and height, analysis results show that the coercive fields for different bottom shapes are of similar values. Designed as a cubic grain,the coercive field presents descending tendency as grain volume ascends. Under constant grain volume,with aspect ratio increasing, the coercive field decreases in the beginning and increases soon. Based on the demagnetization field vector, the effects of bottom shape, grain volume and aspect ratio on the coercive field can be explained. The nucleation point is chosen to discuss. Its synthetic field and reversal field are calculated by parallelogram law and inverse external field equation, respectively. The synthetic field equal to the reversal field is defined as critical field, which always shows the same tendency as the coercive field for all cases of this study. It can be concluded that critical field is qualified to be a reference index to measure the magnitude of coercive field. 相似文献