Phase relations of the (Pr_1−xSm_x)₂Fe₁₄B system

ABSTRACT

The phase relations in the (Pr_1−xSm_x)₂Fe₁₄B system in a whole concentration range have been studied by means of X-ray powder diffraction (XRD), differential thermal analysis (DTA) and scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDS). The XRD patterns of the (Pr_1−xSm_x)₂Fe₁₄B samples have been refined by Rietveld method. These results reveal that all the alloys (Pr_1−xSm_x)₂Fe₁₄B are similar to the end member of the investigated system Pr₂Fe₁₄B with tetragonal structure (space group P4₂/mnm). The continuous solid solutions were formed in this system. The normalized lattice parameters and unit cell volumes of (Pr_1−xSm_x)₂Fe₁₄B solid solutions decrease linearly with x ranging from 0 to 1.0. The DTA measurements show that the peritectic temperature of (Pr_1−xSm_x)₂Fe₁₄B increases with increasing Sm content and no metastable phases are detected. Based on the DTA data, SEM–EDS and XRD results, the vertical section of Pr₂Fe₁₄B–Sm₂Fe₁₄B in the Pr–Sm–Fe–B system has been constructed.

KEYWORDS:

• Phase relations
• (Pr_1−xSm_x)₂Fe₁₄B system
• X-ray powder diffraction
• differential thermal analysis

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Basic Research Program of China [grant number 2014CB643703]; the National Natural Science Foundation of China [grant number 50261002], [grant number 50661002], [grant number 51161005]; Guangxi Natural Science Foundation [grant number 2015GXNSFAA139249]; 2015 Guangxi higher education undergraduate teaching reform project [grant number 2015JGB434].