High content of oxygen in NdFeB magnet is one of the essential factors that hinder its large-scale industry production and cause its low grade in magnetism performance. Therefore, how to control the total oxygen content and oxygen states in NdFeB becomes an important issue brought to analysts. Based on different binding energies of oxides with graphite in the sample, releasing behaviors of different oxides in NdFeB were investigated by both qualitative and quantitative methods in this article. Inert gas fusion infrared absorption method was used in the article. As verified by ramp heating mode, two kinds of oxides were found to exist in Nd2 Fe14 B under different analyzing heating powers. Based on releasing conditions derived from ramp heating mode, two releasing peaks of different oxides obtained from segmented heating mode were completely separated. Then, X-ray diffraction, SEM, Electrolyte distillation and Photoelectron Spectroscopy were used on Nd2Fe14B sample and the 1st- stepheated sample individually. Qualitative analysis results were obtained. The first peak was released from deoxidization of NdxFeyOz compound. The second one was released from Nd2O3 deoxidization. Based on the above results, seriatim calibrated method was used to calibrate the two peaks respectively. Accurate quantitative results of them were obtained.%钕铁硼磁体中氧含量偏高是影响其大工业生产、造成钕铁硼磁体性能偏低的主要原因之一,因此合理地控制氧在钕铁硼中含量及其存在状态,为分析工作提出了重要研究课题.依据样品中不同状态氧与碳的结合能不同的特点,本文使用惰气熔融红外吸收法对钕铁硼材料样品中不同状态氧进行了定性和定量的方法研究.首先通过斜率加热模式,确定钕铁硼样品在不同分析加热电流下存在着两种状态氧化物.根据斜率加热模式下得到的每种状态氧化物对应的释放条件,使用分段加热模式,完全分离两种状态氧的释放峰.对原始样品和第一段加热后的中间产物分别进行X射线衍射、背散射扫描电镜、电解提取氧化物和光电子能谱分析,得到两种状态氧的定性分析结果:第一段加热电流下得到氧的释放峰为钕铁氧的复合物分解释放产物,第二段加热电流下得到的氧的释放峰来源于氧化钕的分解还原.根据文中研究得到的定性分析及定量分离方法,选取相应标准物质对两种氧化物释放峰进行分别标定,得到钕铁硼样品中两种状态氧化物的准确定量结果.
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