Yao Wen-Jing, Sun Wen, Wang Nan, Han Seung Zeon, Lee Je-Hyun
J Nanosci Nanotechnol. 2014 Nov;14(11):8572-7. doi: 10.1166/jnn.2014.9999.
Under near-equilibrium solidification conditions, the Co-17.8 wt%Gd eutectic alloy forms rod-like eutectic microstructure of (αCo) solid solution and Co17Gd2 compound. When the solidification condition is far from the equilibrium, the rapid growth of nano-eutectic in Co-17.8 wt%Gd alloy ribbons is realized by the single-roller techniques. The average granular size (d) of nano-eutectic in the center of ribbons varies with the increase of wheel speed (V), d = 510.36-25.51 V+0.44 V2. XRD results of ribbons at different wheel speeds indicate that, with the rise of wheel speed, the main peak of Co17Gd2 compound becomes more and more notable, whereas the main peak of (αCo) solid solution tends to reduce. Along the length direction, the Co-17.8 wt%Gd alloy ribbons have the negative magnetostrictive strain. The magnetostrictive strain enhances with the increase of wheel speed. At the wheel speed of 40 m/s, the magnetostrictive coefficient of ribbons is measured to be - 733 ppm at the magnetic field of 6 kOe. The influence of the wheel speed and the magnetic field on the maanetostrictive coefficient is discussed.
在近平衡凝固条件下，Co-17.8 wt%Gd共晶合金形成(αCo)固溶体和Co17Gd2化合物的棒状共晶微观结构。当凝固条件远离平衡时，通过单辊技术实现了Co-17.8 wt%Gd合金薄带中纳米共晶的快速生长。薄带中心纳米共晶的平均粒度(d)随辊速(V)的增加而变化，d = 510.36 - 25.51V + 0.44V²。不同辊速下薄带的XRD结果表明，随着辊速的升高，Co17Gd2化合物的主峰变得越来越明显，而(αCo)固溶体的主峰趋于降低。沿长度方向，Co-17.8 wt%Gd合金薄带具有负磁致伸缩应变。磁致伸缩应变随辊速的增加而增强。在辊速为40 m/s时，在6 kOe磁场下测量薄带的磁致伸缩系数为-733 ppm。讨论了辊速和磁场对磁致伸缩系数的影响。
