Magnetic Properties of Nanostructured Rare Earth-Fe Compound Produced by HDDR Process

目的是：持久性增强的磁铁从硬和软磁性相位的两个阶段纳米结构中制造出来，可以由任何熔融旋转或机械合金制备。我们先前的工作表明，还可以通过氢化分解降解重组（HDDR）处理Sm 3（Fe，V）29型TbCu 7型和αFe（V）阶段，其中包括约0.6 MAm D1-1 D1 （7 kOe）后的共同作用。However，HDDR处理材料的颗粒尺寸（~ 300纳米）通常比强度更大，因为它需要增强对时间的持久性：软颗粒理想上应该是10 - 20纳米。Cohas的补充显示出在减少重组温度和颗粒大小的HDDR治疗样品中具有有效性。因此，该工作的目标是调查钴对Sm 3（Fe，V）29的分化和重组动力学的影响，并试图减少Fe（Co，V）/TbCu 7型的颗粒大小。 ... More 相位混合实验程序：Sm9.4Fe84.6-XCoXV 6.0（X=0、10、20和30）的合金，从高纯度元素中熔化，在大气层下，然后在1150 ° C的20小时内均匀化。X射线衍射（XRD）分析显示，合金靠近单个相位Sm 3（Fe，Co，V）29，含一个较小的Fe（Co，V）均匀的合金是进入粉末的基础，覆盖到小于63微米的颗粒尺寸，并被压制成绿色的伴侣。样品在分化反应的不同阶段产生，在620 - 700 ° C之间加热到温度，然后一小时后，在氢中快速冷却。HDDR样品在真空下加热到590 - 750 ° C之间的温度，然后在10分钟- 12小时后冷却，在真空下快速冷却。一些HDDR样品在560 ° C（4小时3）时被点燃，然后进入粉末，在1.0 MAm-1（12 kOe）的磁场中混合了固体石蜡。magnetic properties were measured using a vibrating sample magnetometer （VSM）。传输电子显微镜（TEM）的样本是由离子铣削处理的。结果：加上钴的添加，合金Sm9.4 Fe84.6-XCoXV6.0（X=0、10、20、30）的分解温度增加，重组温度减少。本文显示钴稳定性Sm 3（Fe，Co，V）29阶段，尊重氢中的降解，增加了重组进入Fe（Co，V）和TbCu 7型阶段的速率。With TEM [近似等于] 5 nm直径rods were observed，谁相信是SmH 2。在630 ° C的1小时内发现了约50-100纳米的尺寸，30%的Co样品重新组合。在添加到aFe（Co，V）和TbCu 7型相位中， XRD还显示了仍未识别的相位的存在，这些相位在高钴含量和低温度下存在，似乎对磁性性能有不利影响，在硝化后。Less（低）

Purpose : Remanence enhanced magnets made from a 2 phase nanostructure of hard and soft magnetic phases, can be prepared by either melt spinning or by mechanical alloying. Our previous work has shown that a 2 phase mixture can also be obtained by the Hydrogenation Disproportionation Desorption Recombination (HDDR) processing of Sm3(Fe,V)29 into TbCu7 type and αFe(V) phases, which exhibits coercivities of about 0.6 MAmィイD1-1ィエD1 (7kOe) after nitriding. However, the grain size of HDDR processed materials (〜300 nm) is typically an order of magnitude larger than that necessary for remanence enhancement to occur : the soft grains should ideally be 10 - 20 nm. The addition of Co has been shown to be effective in reducing the recombination temperature and grain size of HDDR treated samples. Therefore, the aim of this work was to investigate the effect of Co on the disproportionation and recombination kinetics of Sm3(Fe,V)29, and to attempt to reduce the grain size of the aFe(Co,V)/TbCu7 type … More phase mixture.Experimental Procedure : Alloys of Sm9.4Fe84.6-XCoXV6.0 (X=0, 10, 20 and 30), were induction melted from high purity elements, under an Ar atmosphere, and then homogenized at 1150℃ for 20 hours. X-ray diffraction (XRD) analysis showed that the alloys were near single phase Sm3(Fe,Co,V)29 with a small amount of aFe(Co,V). The homogenized alloys were ground into powders, sieved to a particle size less than 63μm, and pressed into green compacts. Samples were obtained at different stages of the disproportionation reaction, by heating under hydrogen to temperatures between 620 - 700℃, and then after 1 hour, cooling rapidly in hydrogen. HDDR samples were obtained by heating the disproportionated samples under vacuum to temperatures between 590 - 750℃, and then after 10 min - 12 hours, cooling rapidly under vacuum. Some of the HDDR samples were then nitrided at 560℃ for 4 hours 3), then ground into powder, which was mixed with molten paraffin that solidified within a magnetic field of 1.0 MAm-1(12 kOe). The magnetic properties were measured using a vibrating sample magnetometer (VSM). Samples for transmission electron microscopy (TEM) were thinned by ion milling.Results : with the addition of cobalt, the disproportionation temperature of the alloys Sm9.4Fe84.6-XCoXV6.0 (X=0, 10, 20, 30) increased, and the recombination temperature decreased. This shows that cobalt stabilizes the Sm3(Fe,Co,V)29 phase with respect to disproportionation in hydrogen, and increases the rate of the recombination into aFe(Co,V) and TbCu7 type phases. With TEM 【approximately equal】5 nm diameter rods were observed, which are believed to be SmH2. Grains about 50-100 nm in size were found in a 30% Co sample recombined at 630℃ for 1 hour. In addition to aFe(Co,V) and TbCu7 type phases, XRD also showed the presence of a yet unidentified phase that forms at high Co contents and low temperatures, which appeared to have an adverse effect on the magnetic properties, after nitriding. Less