摘要
SmFealloy is the intermediate material for the preparation of SmFeNx(x ≈ 3); thus, the synthesis of pure SmFemother alloy is the key to obtaining highperformance SmFeNx. Reduction-diffusion(R-D) is a cost-effective method. In this study, the R-D process of synthesizing SmFewas analyzed by scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), and X-ray fluorescence(XRF). Furthermore, the influences of the tightness of compacted reactants, the compensation amount of SmO,and the particle size of Fe on the formation of SmFewere discussed from the aspects of the three raw materials.The results show that Sm reduced from SmOreacts with Fe particles to form intermetallic compound SmFedirectly in the R-D reaction process of preparing SmFe;the generation of Sm and its migration to the surface of Fe particles control the reaction rate; a proper tightness of compacted reactants is necessary for ensuring the purity of SmFeproduct; pure SmFecan be obtained when the compensation of SmOis 33 % of the stoichiometry; and the sufficiency of the reaction improves with the decrease in the size of Fe powders under the same reaction condition.
Sm_2Fe_(17) alloy is the intermediate material for the preparation of Sm_2Fe_(17) Nx(x ≈ 3); thus, the synthesis of pure Sm_2Fe_(17) mother alloy is the key to obtaining highperformance Sm_2Fe_(17) Nx. Reduction-diffusion(R-D) is a cost-effective method. In this study, the R-D process of synthesizing Sm_2Fe_(17) was analyzed by scanning electron microscopy(SEM), energy-dispersive X-ray spectroscopy(EDX), X-ray diffraction(XRD), and X-ray fluorescence(XRF). Furthermore, the influences of the tightness of compacted reactants, the compensation amount of Sm_2 O_3,and the particle size of Fe on the formation of Sm_2Fe_(17) were discussed from the aspects of the three raw materials.The results show that Sm reduced from Sm_2 O_3 reacts with Fe particles to form intermetallic compound Sm_2Fe_(17) directly in the R-D reaction process of preparing Sm_2Fe_(17);the generation of Sm and its migration to the surface of Fe particles control the reaction rate; a proper tightness of compacted reactants is necessary for ensuring the purity of Sm_2Fe_(17) product; pure Sm_2Fe_(17) can be obtained when the compensation of Sm_2 O_3 is 33 % of the stoichiometry; and the sufficiency of the reaction improves with the decrease in the size of Fe powders under the same reaction condition.
基金
financially supported by the Natural Science Foundation of Zhejiang Province, China (No. Y406406)
the Xinmiao Talent Project of Zhejiang Province, China (No. 2014R403057)
