铁基非晶合金的取向纳米晶化及其力学与磁性能研究

Fe-based amorphous and nanocrystalline alloys are the third generation of soft magnetic materials according to their excellent SMPs. They have been used in electric and electronic field, and they were much more applicable for their high efficiency in motor due to the requirement of energy-saving and emission-reducing, and flourish of electric vehicle. Nowadays used amorphous/ nanocrystalline alloys still have problems such as the relatively low saturated magnetic flux density and induced brittleness. There still no applicable amorphous/nanocrystalline alloys with high Bs near 1.7 T as the high cost and low glass forming ability. Aiming at these problems, FePC, FeSiBPC and FeSiBPNbCu amorphous alloys were chosen for their combining high glass forming ability and high saturated magnetic flux density. The higher Bs can be realized for the formation of bcc-Fe nanocrystals after annealing. The orientation effects on the SMPs and mechanical properties will be systematically studied, the orientation role on the SMPs and mechanical properties will be given. Depending on the neutron scattering, the microstructure and the magnetic structure will be clear. The mechanism of orientation effects on the SMPs and mechanical properties will be revealed.

由于现代化社会对节能和减排提出了要求的更高，电动汽车的蓬勃发展给非晶/纳米晶材料在电机上的应用提供了强劲的增长点。本研究面向目前产业上使用的非晶/纳米晶材料存在饱和磁感应强度低和脆性大等问题，选取前期研究成果的高非晶形成能力和高饱和磁感应强度的合金作为研究的基体材料，调整各元素含量得到适合制备纳米晶的成分，进行磁场辅助的快速热处理，使合金形成具有不同取向的纳米晶结构，以此来获得高饱和磁感应强度。并系统研究不同取向程度纳米晶合金的软磁性能和力学性能，获得晶粒取向对非晶/纳米晶材料性能的影响规律，通过散列中子技术研究非晶/纳米晶材料的微观结构和磁结构，进而揭示取向纳米晶化对非晶/纳米晶材料磁性能和力学性能的影响机理。

软磁非晶合金在电力电子等领域已经取得大量的应用，新型的非晶合金电机有可能作为新的应用增长点。为满足新型非晶电机对非晶材料更高的性能要求，需要开发出具有高饱和磁感应强度和高非晶形成能力的非晶合金成分。为进一步提高材料的性能，拟在非晶合金的基础上，通过快速热处理，使非晶合金纳米晶化，通过磁场调整其纳米晶的取向，进一步提高其软磁性能，降低材料因长时间热处理带来的脆性。本项目按计划完成了非晶合金成分的探索，在Fe83Si2B11P3C1非晶合金的基础上，通过Co，Ni等元素的调整，获得了高饱和磁感应强度的非晶合金。重点研究用磁场热处理（施加磁场的大小和方向、热处理温度和时间等对合金取向纳米晶化结构和性能的影响），以获得优异的软磁性能，并研究了磁场对磁性能影响的机理。. 通过高饱和磁感应强度的纳米晶合金的选取和制备，在合金体系中，通过调整Fe含量和类金属元素的含量，筛选出两晶化峰温度宽的合金成分，获得了兼具高非晶形成能力和高饱和磁感应强度的合金成分。通过调整了施加磁场的大小和方向、热处理温度和时间等条件，研究了各因素等对纳米晶磁畴取向的影响。本项目的研究结果为开发具有应用前景的高非晶形成能力和高饱和磁感应强度非晶合金提供实验科学依据，为磁场对非晶合金的取向纳米晶化提供一定的工艺支撑。