In this work, the (1-x)CaWO₄-xNa₂WO₄ (x = 0.1, 0.2, denoted as 0.9CW-0.1NW and 0.8CW-0.2NW, respectively) ultralow-loss microwave dielectric ceramics were prepared via solid-state reaction method. Using low melting-point Na₂WO₄ as sintering aid to prepare CaWO₄Na₂WO₄ composite ceramics, the sintering temperature of CaWO₄ was successfully reduced while maintaining excellent microwave performance. The optimal microwave dielectric properties have been achieved at 900 °C for 0.9CW-0.1NW ceramic: ε_r = 9.0, Q × f = 105660 GHz, tanδ = 1.1 × 10⁻⁴ and τ_f = −35.4 ppm/°C at a frequency of 12.0 GHz. For the 0.8CW-0.2NW ceramic, the optimal microwave dielectric properties have been obtained at 740 °C, with ε_r = 8.5, Q × f = 97014 GHz, tanδ = 1.2 × 10⁻⁴ and τ_f = −37.4 ppm/°C at a frequency of 11.8 GHz. In summary, both composite ceramics exhibit low sintering temperatures, excellent dielectric properties and chemical compatibility with the Ag electrode. The findings of this study provide an effective approach to prepare novel composite ceramics as promising candidates for LTCC applications.

在这项工作中，(1- x )CaWO ₄ - x Na ₂ WO ₄ ( x  = 0.1, 0.2，分别表示为 0.9CW-0.1NW 和 0.8CW-0.2NW) 超低损耗微波介电陶瓷是通过以下方式制备的：固态反应法。以低熔点Na ₂ WO ₄为烧结助剂制备CaWO ₄ Na ₂ WO ₄复合陶瓷，在保持优良微波性能的同时，成功降低了CaWO ₄的烧结温度。对于 0.9CW-0.1NW 陶瓷，在 900 °C 下已实现最佳微波介电性能：ε _r = 9.0，Q × f = 105660 GHz，tanδ = 1.1 × 10 ^-4和 τ _f  = -35.4 ppm/°C，频率为 12.0 GHz。对于 0.8CW-0.2NW 陶瓷，最佳微波介电性能在 740 °C 下获得，ε _r  = 8.5，Q × f = 97014 GHz，tanδ = 1.2 × 10 ^-4和 τ _f  = -37.4 ppm/ °C，频率为 11.8 GHz。总之，这两种复合陶瓷都表现出低烧结温度、优异的介电性能和与银电极的化学相容性。这项研究的结果提供了一种有效的方法来制备新型复合陶瓷，作为 LTCC 应用的有希望的候选者。