Interactions between chemical ordering and magnetic transitions in ferromagnetic alloys.

铁磁合金中化学排序和磁转变之间的相互作用。

基本信息

批准号：
11450233
负责人：
KAINUMA Ryosuke
金额：
$ 9.34万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B).
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2000
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11450233/
关键词：
PHASE SEPARATION ORDER-DISORDER TRANSITIONS MAGNETIC TRANSITION Fe-Al SYSTEM Fe-Ga SYSTEM Co-Al BASE SYSTEMS THERMODYNAMICS PHASE DIAGRAMS Fe-Si合金 Fe-Ga合金

项目摘要

It is known that magnetic transition influences order-disorder transitions in the Fe-base alloys which show both the chemical ordering and magnetic transition. However, there are very few papers quantitatively discussing the interactions between those transitions. In the present project, the order-disorder and magnetic transition temperatures in some Fe-base and Co-base alloys has been examined and the interaction between them was evaluated by thermodynamic calculation using the CALPHAD-type and BWG analysis.In order to investigate this topic, the Fe-X (X : Al, Rh, Ga and Si) systems and the Co-Al-X (X : Ti, Ni) systems had been selected. The obtained results are as follows :(1) The magnetic and chemical ordering transition temperatures in the Fe-X (X : Al, Rh, Ga, Si) binary alloys were determined by VSM, differential scanning calorimetry (DSC) and electric resistance (ER) measurements. In the case of some alloys showing the 1st order transitions, the phase equilibrium between the ordered and disordered phases were examined by X-ray microanalysis (XMA) and transmission electron microscopy (TEM). It was clarified by these examinations that the interactions between the magnetic and chemical orderings exist there in the Fe-Al and Fe-Ga systems.(2) The magnetic and chemical ordering transition temperatures in the Co-Al-X (X : Ti, Ni) ternary alloys were also determined by VSM and DSC measurements. The phase equilibrium between the B2 and D03 phases were examined by TEM observation.(3) On the basis of those experimental results, the phase equilibria in the Fe-Rh and Fe-Al binary systems were analyzed using the CALPHAD-type thermodynamic calculation. In conclusions, it was proposed that since the magnetic properties are strongly affected by the degree of order in the ordered phase, and the new thermodynamic model which takes into account the interaction between the magnetic and chemical orderings should be used for precisely describing the phase stability of phases.

众所周知，磁过渡会影响Fe碱合金中的顺序降级转变，该合金既显示化学秩序和磁过渡。但是，很少有论文定量地讨论这些过渡之间的相互作用。在本项目中，已经检查了某些Fe基和共同基础合金中的顺序序列和磁过渡温度，并通过使用calphad-type和BWG分析通过热力学计算来评估它们之间的相互作用。获得的结果如下：（1）Fe-X（X：Al，Rh，Ga，Ga，Si）中的磁和化学排序过渡温度通过VSM确定，二元合金，差分扫描量热法（DSC）和电阻（ER）测量值。如果某些合金显示一阶跃迁，则通过X射线微分析（XMA）和透射电子显微镜（TEM）检查有序相和无序相之间的相平衡。通过这些检查阐明了磁性和化学有序之间存在的Fe-AL和Fe-GA系统中存在的相互作用。（2）CO-AL-X（X：TI，Ni）三元合金中的磁和化学顺序过渡温度也由VSM和DSC测量确定。通过TEM观察检查了B2和D03相之间的相位平衡。（3）基于这些实验结果，使用Calphad-type热力学计算分析了Fe-RH和Fe-Al Binary Systems中的相位平衡。总而言之，有人提出，由于磁性在有序阶段中受到有序程度的强烈影响，并且新的热力学模型考虑了磁性和化学有序之间的相互作用，以精确描述相相位的相位稳定性。