Atomistic simulations of advanced permanent magnet materials

在从汽车到风力发电机的技术中，由于其在将电能转换为机械运动或相反的过程中的固有效率，钕永磁体无处不在。由于这种效率，今天的主要应用是混合动力汽车和风力涡轮机，这两种汽车在英国都有强大的制造基地。基于TmMn12(RETM12)结构的下一代稀土-过渡金属永磁材料为将材料的能效提高一倍提供了令人兴奋的机会。再加上新的电机设计，就有可能将相同电池尺寸的风力涡轮机或混合动力汽车的输出功率提高一倍[1]。然而，要了解这种材料的性质，就需要对这种材料及其与温度相关的性质建立新的模型。此外，需要充分了解和优化材料的界面性质，以获得高性能。本项目的目的是开发新的TmMn12基永磁材料的原子学模型，以预测其性能和了解其基本磁性能。这些模型将用于指导工业磁体生产，以加快发展具有超高能效的下一代磁体。具体地说，我们将发展一个新的RETM12结构永磁体的原子自旋模型，该模型考虑了稀土替代和界面的影响。这些模型将被用来模拟它们的静态和动态磁特性，以评估它们在混合动力汽车和风力涡轮机中的应用潜力。材料的合金化性质增加了显着的复杂性，需要仔细的参数设置和根据实验数据进行验证。这将建立一种新的计算能力，使永磁体材料的模拟成为可能，如果商业上成功，可能会对全球经济产生影响。[1]Oliver Gutfleisch等人，高级Mater。23,821-842(2011)

Neodymium permanent magnets are ubiquitous in technologies from cars to wind generators due to their inherent efficiency in converting electrical power to mechanical motion or vice versa. Due to this efficiency the main applications today are in hybrid electric cars and wind turbines, both of which have a strong manufacturing base in the UK. Next generation rare-earth-transition metal permanent magnet materials based on the TmMn12 (RETM12) structure present an exciting opportunity to double the energy efficiency of the materials. Coupled with new motor designs this presents the possibility of doubling the power output of a wind turbine or range of hybrid car with the same battery size [1]. However, understanding the properties of the material will require new models of the material and its temperature dependent properties. In addition, the interface properties of the material need to be fully understood and optimized to achieve high performance.The aim of this project is to develop new atomistic models of TmMn12-based permanent magnet materials to predict their performance and understand the fundamental magnetic properties. These models will be used to guide industrial magnet production to accelerate the development of next generation magnets with ultrahigh energy efficiency. Specifically, we will develop a new atomistic spin model of RETM12 structured permanent magnets including the effects of RE substitution and interfaces. These models will be used to model their static and dynamic magnetic properties to evaluate their potential for applications in hybrid electric cars and wind turbines. The alloyed nature of the material adds significant complexity and requires careful parameterisation and validation against experimental data. This will establish a new computational capability enabling simulations of permanent magnet materials and if commercially successful could have a worldwide economic impact.[1] Oliver Gutfleisch et al, Adv. Mater. 23, 821-842 (2011)