采用固相反应法制备(Mg 1-x Znx)2 SiO4 (0≤x≤1)微波介质陶瓷, 研究(Mg 1-x Znx)2 SiO4 陶瓷在0≤x≤1范围内的相演变、微结构与其微波介电性能间相互关系. XRD测试结果表明：橄榄石结构的Mg2SiO4与硅矽矿结构的Zn2SiO4在晶体结构上存在很大差别, (Mg, Zn)2 SiO4在0≤x≤1范围内只能部分地实现有限固溶. 背散射电子扫描显微镜（BESEM）测试结果显示：随着x的增加, MgSiO3第二相得到抑制; 陶瓷出现液相烧结, 促进晶粒生长与玻璃相在晶界处沉积. 微波介电性能测试结果表明：由于Zn 2+离子极化能力大于Mg 2+离子, (Mg 1-x Znx)2 SiO4 (0≤x≤1)陶瓷介电常数随x值增加而增大; 0≤
x≤1范围内, Mg2SiO4陶瓷微波性能由于第二相、气孔率增加与晶粒增大而降低, Zn2SiO4陶瓷由于微结构得到改善, 陶瓷微波性能得到优化. 当x=0.6时, 得到较好的(Mg 0.4 Zn 0.6)2 SiO4 陶瓷微波性能为：εr=6.6, Qf=95650GHz,τf=-60×10-6/℃
The phase evolutions, microstructures, and microwave dielectric properties of (Mg 1-x Znx)2 SiO4 (0≤x≤1) ceramics were investigated. The XRD results show that Mg2SiO4 and Zn2SiO4 are partly limited solid solution in the systems of (Mg 1-x Znx)2 SiO4 ceramics, due to the large differences between their crystal structures. BESEM images show that with the increases of x, the second phase of MgSiO3 will be suppressed, and the occurrence of liquid phase sintering accelerates the growth of crystal grain and aggradations of glass phase in the boundary of grain. The dielectric constants of (Mg 1-x Znx)2 SiO4 ceramics gradually increase because of the polarization of Zn 2+ ion is larger than that of Mg 2+ ion. The microwave properties of (Mg 1-x Znx)2 SiO4 ceramics change with the variant of x value, together with external factors of the secondary phase, porosity and grain size of(Mg 1-x Znx)2 SiO4 ceramics. When x is equal to 0.6, the optimum microwave dielectric properties of (Mg 0.4 Zn 0.6 )2 SiO 4 ceramics is obtained：εr=6.6, Qf=95650GHz, τf=-60×10-6 /℃.
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