粘结磁体助剂对模压成型NdFeB粘结磁体性能的影响

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.     

粉末粒度对注射粘结磁体性能的影响

实验分析了粉末粒度对制得的注射粘结磁体密度、取向度和磁性能的影响,得出了磁粉粒径太大和太小均不利于磁体磁性能的提高的结论．同时,通过搭配不同比例的粉末,可以提高磁体的装载量,从而达到提高磁性能的目的．     

NdFeB粘结磁体加工性能

应用高压毛细管流变仪和HAAKE转矩流变仪，研究了粘结剂尼龙．6质量分数10％时的NdFeB粘结磁体流变和加工性能。结果表明：NdFeB粘结磁性材料的喂料体系的流动为非牛顿型假塑性液体，具有超高的熔体粘度；润滑剂能有效地降低喂料流动粘度，改善加工条件；而偶联剂会恶化其加工性能；磁粉的粒度分布对喂料的粘度和加工性能有明显的影响。本实验结果可为NdFeB粘结磁体注射、挤出成型的工艺参数确定、模具和机械设计以及加工质量的控制等提供技术依据。     

FL对丁腈橡胶粘结磁体性能的影响

采用平衡溶胀法、力学性能测试及高低温老化试验等方法，研究不饱和双键高活性脂肪酸锌盐——FL对丁腈橡胶粘结磁体力学性能以及老化性能的影响．结果表明加入FL后提高了混炼胶的流动性，体系综合力学性能显著提高，硫化橡胶磁体的耐老化性也得到改善．分析了FL的作用机理．     

影响压延取向粘结磁体性能的因素

从分析压延取向对粘结磁体矫顽力等的机制入手,通过扫描电镜、图象仪等工龄研究了影响磁粉形貌及磁体性能的因素,结果表明：磁粉颗粒的径厚比（D／H）是影响磁体性能的关键因素,合适的径厚比能使 粉在取向过程中获得最大有效的取向力矩,同时又能使该应力所引起的晶格畸变最小,获得综合性能优越的磁体;还他磁粉预烧温度、混料方式、预烧助溶剂以及磁体压延取向工艺的混炼温度对磁体性能的影响,为制造磁粉和磁体提供工艺依据。     

稀土粘结磁体的新进展

介绍了新开发的稀土粘结磁体 (各向同性Nd Fe B系、各向异性Nd Fe B系、Sm Fe N系、交换弹簧类等 )的产品及制造工艺。还给出了稀土粘结磁体的一些最新研究结果。     

工艺参数对注射成形各向异性粘结NdFeB磁体性能的影响

研究了注射温度、模具温度、注射压力及注射速度对注射成形各向异性粘结NdFeB磁体的磁性能及力学性能的影响，并分析了其原因。结果表明：注射温度及模具温度对磁体磁性能影响较大，而注射压力则对磁体的抗压强度影响较大。在最佳的注射参数下，获得了最大磁能积和抗压强度分别为90kJ／m^3及130MPa的高性能粘结磁体。     

磁粉及其偶联处理对压延取向橡胶粘结磁体性能的影响

通过对压延取向橡胶粘结磁体的磁性能及力学性能的测量和在扫描电镜上对磁粉颗粒形貌及粘结磁体拉伸断口形貌的观察研究，表明同样条件下，磁粉径厚比分布合理是保证粘结磁体性能的关键。磁粉大小均匀，径厚比大约在3．0～4．0之间时，磁体综合性能良好；偶联剂的种类及偶联处理工艺也对磁体性能有重要影响。     

耐热耐油性能优异的粘结铁氧体磁体的研制

以NBR并用CPE作为粘结剂，选取合适的配方体系及流化体系．采用平板硫化工艺，选取适当的硫化条件．如温度、时间、压力，可制取耐热、耐油性能优异且耐屈挠性好的NBR磁体     

YZT13B磁胶条综合性能的改善

试验分析了成份不同的配比、不同的粘结剂类型和工艺对磁胶条磁性能和物理性能的影响，结果表明：质量分数90％磁粉、8％CPE、2％添加剂配比的YZT13B磁胶条综合性能满足使用要求；而8％CPE中采用70％135A型和CPE与30％B型CPE对物理性能提高效果显著而磁性能满足要求；40％-50％压下量可以获得较佳综合性能。     

模压成形各向异性NdFeB粘结磁体性能研究

采用模压成形方法制备各向异性粘结NdFeB磁体,主要研究了粉末粒度以及取向磁场强度对粘结磁体磁性能和力学性能的影响.试验结果表明,随着磁粉粒度的减小,粘结磁体的剩磁有所增加,但矫顽力下降明显.随着取向磁场强度的增大,粘结磁体剩磁进一步提高,各向异性明显;粘结磁体密度及抗压强度随磁粉粒度的减小略有提高.经粒度配比后制备的粘结磁体获得了较高的磁性能和抗压强度,其B_r、H_(ci)及σ_(bc)分别为0.81T、828kA/m及204MPa.     

成形工艺对粘结NdFeB磁体结构和磁性能的影响

在粘结NdFeB磁体模压成形过程中存在较大的压力损失，引起磁体密度分布不均匀，致使磁体密度减小。本文研究了压制压强、预压成形和压制方式等对粘结NdFeB磁体结构和磁性能的影响及机理。研究表明：随着压制压强提高，粘结NdFeB磁体的密度和磁性能显著增大；粒度配合、预压成形和双向压制等办法均可增大粘结NdFeB磁体的密度和磁性能；在适当的压制压强下，将粒度配合、预压成形及双向压制工艺结合，制备出密度达到6．5g／cm^3、磁能积达到104kJ／m^3的粘结NdFeB磁体。     

橡塑磁体的研究发展现状

本文分别就橡塑磁体的磁粉、粘结剂和配合剂等的研究发展现状作了介绍,并对橡塑磁体需要进一步解决和研究的问题提出了几点看法.     

Magnetic property recovery in Nd-Fe-B bonded magnet wastes with chemical reaction and physical dissolution

The main difficulty for the recovery of Nd-Fe-B bonded magnet wastes is how to completely remove the epoxy resins. In this study, chemical reaction and physical dissolution were combined to remove the epoxy resins by adding ammonia-water and mixed organic solvents. Ammonia-water can react with the epoxy functional group of epoxy resin to generate polyols. Mixed organic solvents of alcohol, dimethyl formamide (DMF), and tetrahydrofuran (THF) can dissolve the generated polyols and residual epoxy resins. Under the optimum processing conditions, the epoxy resins in the waste magnetic powders are substantially removed. The oxygen and carbon contents in the recycled magnetic powder are reduced from 13500 × 10⁻⁶ to 1600 × 10⁻⁶ and from 19500 × 10⁻⁶ to 2100 × 10⁻⁶ with the reduction ratio of 88.1% and 89.2%, respectively. The recycled magnetic powder presents improved magnetic properties with M_s of 1.306 × 10⁻¹ A∙m²/g, M_r of 0.926 × 10⁻¹ A∙m²/g, H_cj of 1.170 T, and (BH)_max of 125.732 kJ/m³, which reach 99.8%, 99.4%, 95.9%, and 96.9% of the original magnetic powders, respectively.     

成型工艺对粘结钕铁硼永磁材料磁性能的影响

采用由熔体快淬法制备的不同粒度大小的M Q粉搭配,分别与粘结剂和一些助剂(固化剂、润滑剂等)按照一定的比例混合,放入模具中,在不同压力下压制成所需要的形状,加热到一定的温度固化。结果表明,磁粉的粒度搭配、成型压力是影响磁性能的重要参数。     

Effect of silane coupling agents on flowability and compressibility of compound for bonded NdFeB magnet

Based on the difference of the Y-terminal functional group of the silane coupling agent (Y–Si(X)₃), four different silane coupling agents were employed to pretreat the surface of the NdFeB powders. The effects of silane coupling agents on the flowability and compressibility of compounds for preparing bonded NdFeB magnets were studied. It is indicated that compounds pretreated by silane coupling agents have weaker friction and meshing force. The apparent density is increased by 0.3 g/cm³ compared with the compound without silane coupling agent, and the radial crushing strength is significantly increased by about 3–4 times. In addition, the epoxy resin is more evenly distributed on the surface of the compounds treated by silane coupling agents observed by scanning electron microscopy, and some agglomerated particles are produced. Also, the compressibility of compounds with silane coupling agents is significantly improved due to the fact that hardening exponents are reduced. However, the addition of silane coupling agents has almost no effect on the magnetic properties of bonded magnets. The special energy was used to manifest the flowability of magnetic powder particles representing the macroscopic performance of the force between powder particles, providing a new direction for the study of the interface compatibility of two-phase or multiphase composite materials.