Bhale Pranav, Ari-Gur Pnina, Noebe Ronald D, Ren Yang, Madiligama Amila, Devaraj Ranjith, Cook Matthew S
Department of Mechanical and Aerospace Engineering, Western Michigan University, Kalamazoo, MI 49008, USA.
NASA Glenn Research Center, Cleveland, OH 44135, USA.
Materials (Basel). 2023 Oct 7;16(19):6590. doi: 10.3390/ma16196590.
Ni-Mn-based Heusler alloys are known to demonstrate magnetic shape memory and giant magnetocaloric effect (MCE). These effects depend on the phases, crystallographic and magnetic phase transitions, and the crystallographic texture characteristics. These structural characteristics, in turn, are a function of the processing parameters. In the current work, NiMnGaSi Heusler alloy was processed by melt-spinning under a helium atmosphere. This process results in a fine microstructure. The ribbon that was produced with a narrower nozzle width, faster wheel speed, and higher cast temperature, indicating a faster cooling rate, had double the magnetic entropy change close to room temperature. However, the other ribbon demonstrated a large entropy change over a broader temperature range, extending its usability. The effect of the melt-spinning process parameters on the developing microstructure, crystallographic structure and texture, transformation temperatures, and the magnetic entropy change were studied to explain the difference in magnetocaloric behavior.
镍锰基赫斯勒合金以展现磁形状记忆和巨磁热效应（MCE）而闻名。这些效应取决于相、晶体学和磁相变以及晶体学织构特征。反过来，这些结构特征又是加工参数的函数。在当前工作中，NiMnGaSi赫斯勒合金在氦气气氛下通过熔体纺丝进行加工。这个过程会产生精细的微观结构。使用较窄喷嘴宽度、较快轮速和较高铸造温度生产的薄带，表明冷却速度更快，其在接近室温时的磁熵变增加了一倍。然而，另一条薄带在更宽的温度范围内表现出较大的熵变，扩大了其适用性。研究了熔体纺丝工艺参数对微观结构发展、晶体结构和织构、转变温度以及磁熵变的影响，以解释磁热行为的差异。
