【摘 要】
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We investigated the impure phase problem and summarized its two formation mechanisms of YAG powders synthesized via the co-precipitation method. The ions loss problem caused by high concentration reaction solution in the titration process was emphatically
【机 构】
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College of Physics and Electronic Engineering,Nanyang Normal University,Nanyang 473061,China;Departm
【出 处】
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武汉理工大学学报（材料科学版）（英文版）
论文部分内容阅读
We investigated the impure phase problem and summarized its two formation mechanisms of YAG powders synthesized via the co-precipitation method. The ions loss problem caused by high concentration reaction solution in the titration process was emphatically studied, and the corresponding thermodynamic explanation was carried out. In addition, influence of powder crystallinity and its new qualitative and quantitative standards were studied. One reason of impure phase is the local nonuniform mixture of Y and Al elements in precursor, which easily causes intermediate phases during calcination and difficulty of high pure powders at low temperatures. The other reason is the precipitation dissolution during titration and then the Y3+/Al3+ loss, caused by high concentration of reaction solution. The powder crystallinity can be promoted by increasing calcination temperature or holding time of precursor. Besides the routine XRD method, the TEMEDX method should be also introduced to directly determine the quality of crystallinity.
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