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近零及负热膨胀材料有诸多的潜在应用领域,而具有负热膨胀效应的A2M3O12系列材料在较宽的温度范围,易于通过组份变化调整其热膨胀系数.本文首次使用共沉淀法合成了Al2-xYxw3O12(x=0~2)系列粉体材料.经X射线衍射分析证明Al2W3O12和Y2W3O12能完全固溶形成二元固溶体,采用PowderX软件对Al2-xYxW3O12的晶胞参数进行计算,结果表明室温下随着稀土钇(Y)含量的增加,晶体的晶胞参数与晶胞体积逐渐增加.高温X射线衍射结果表明,随着稀土钇(Y)含量的增加,Al2-xYxW3O12的本征热膨胀系数逐渐由正到负变化.热机械分析(TMA)压缩法测定其宏观热膨胀系数,发现通过调整材料的组成,可以将其热膨胀系数控制为一定的正值、负值或零.但是由于其结构的各向异性,多晶陶瓷内部存在的微裂纹使热膨胀曲线出现较大的滞后环.

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