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通过固相反应法,在1100℃下成功制备出了系列Ga掺杂Sc2-xGaxW3O12(x=0,0.05,0.1,0.2,0.3,0.5,0.8)固溶体.X射线粉末衍射结构精修表明,Ga以替代Sc的形式成功进入Sc2-xGaxW3O12晶格,但不能获得端元组分Ga2W3O12化合物.晶胞参数的精修结果表明所有样品均具有负膨胀性能;随着Ga掺杂量的增加,固溶体Sc2-xGaxW3O12的晶胞参数a,c及晶胞体积随之收缩,而晶胞参数b则随之增大,固溶体Sc2-xGaxW3O12的平均体膨胀系数绝对值随之减小.在室温—300℃之间,随着温度的增加,体积膨胀系数绝对值急剧减小,而在300—800℃之间基本保持稳定,当温度大于800℃时,体积膨胀系数绝对值继续减小,逐渐向零膨胀靠近,并具有向正膨胀转化的趋势.
A series of Ga-doped solid solutions of Sc2-xGaxW3O12 (x = 0,0.05,0.1,0.2,0.3,0.5,0.8) have been successfully prepared by solid-state reaction at 1100 ° C. The X-ray powder diffraction structure refinement shows that Ga The successful substitution of Sc into the lattice of Sc2-xGaxW3O12, but can not get the terminal component Ga2W3O12 compound.Precision of the cell parameters showed that all samples have negative expansion properties; with the increase of Ga doping, the solid solution Sc2 -xGaxW3O12 unit cell parameters a, c and cell volume shrinks, while the cell parameters b then increases, the average solid solution Sc2-xGaxW3O12 the absolute value of the average body thermal expansion decreases at room temperature -300 ℃ , With the increase of temperature, the absolute value of volume expansion coefficient decreases sharply, while it basically remains stable between 300-800 ℃. When the temperature is higher than 800 ℃, the absolute value of volume expansion coefficient continues to decrease and gradually approaches zero expansion , And has the tendency to convert to positive expansion.