SBIR Phase I: Pulsed Plasma Atomization of Rapidly Solidified Hard Magnetic Nanophase Nd-Fe-B Powders

这个小型企业创新研究(SBIR)第一阶段项目将探索一种新的技术，以经济的方式合成直径在1-10米范围内的快速凝固磁性(ND-Fe-B)粉末。在使用脉冲等离子射流雾化金属熔体气流的初步实验中，该公司已经生产出了直径达数百纳米的球形铜粉。这些脉冲等离子体射流产生的动量通量比传统的气体雾化高2到3个数量级，从而可以生产出微细粉末。该项目的目标是使用一种根本不同的配置，这种配置更适合生产快速凝固的硬磁纳米粉末。这将通过将脉冲等离子射流耦合到脉冲丝弧金属源而不是更传统的熔体流源来实现。这具有在加工过程中消除材料不相容的预期优势，并避免了对大型感应熔化系统的需要。它还可以提供对重复脉冲等离子射流的可控耦合，允许生产难熔金属粉末，并提供更容易进入雾化区的途径，以提高雾化粉末的冷却速度。该项目将与犹他大学合作进行，该大学将提供硬磁材料加工-微结构-性能关系方面的专业知识。永磁体的商业应用几乎覆盖了技术的每一个角落，包括汽车、计算机、医疗技术、发电设备、航空航天和电信行业。这些磁铁用于紧凑、强大的电动马达，用于计算机磁盘驱动器和电传飞机。它们还被用作高精度致动器，用于光盘播放器中的激光聚焦和个人立体声音响的微型扬声器。汽车应用包括起动器、小型电机、交流发电机、传感器、仪表以及电动和混合动力汽车推进系统。

This Small Business Innovation Research (SBIR) Phase I project will investigate a new technique to economically synthesize rapidly solidified magnetic (Nd-Fe-B) powders with diameters in the 1-10 m range. In preliminary experiments using pulsed plasma jets to atomize metal melt streams, the company has produced spherical copper powders down to several hundred nanometers. These pulsed plasma jets produce momentum fluxes 2 to 3 orders of magnitude higher than conventional gas atomization, thus allowing production of fine powders. The objective of this project is to use a fundamentally different configuration, which is more amenable to the production of rapidly solidified hard magnetic nanophase powders. This will be accomplished by coupling the pulsed plasma jet to a pulsed wire arc metal source instead of the more conventional melt stream source. This has the anticipated advantage of eliminating material incompatibilities during processing and avoids the need for large induction melt systems. It can also provide controllable coupling to a repetitively pulsed plasma jet, allow production of refractory metal powders, and provide easier access to the atomization zone for enhancing the cooling rate of the atomized powders. The project will be carried out in cooperation with the University of Utah, which will provide expertise in processing-microstructure-property relationships in hard magnetic materials. Commercial applications of permanent magnets reach virtually every corner of technology, including automobiles, computers, medical technology, power generation equipment, aerospace, and telecommunication industries. These magnets are used in compact powerful electric motors for computer disk drives and fly-by-wire aircraft. They are also find applications as high precision actuators used to focus the laser in a compact disk player and in miniature loudspeakers of personal stereos. Automotive applications include starters, small motors, alternators, sensors, meters, and electric and hybrid vehicle propulsion systems.