高膨胀系数玻璃-陶瓷复合材料的性能研究

选用具有良好介电性能和膨胀性能的硼硅酸盐(SiO2-BaO-B2O3-Al2O3)和石英,采用固相法合成了一系列具有高热膨胀系数的玻璃-陶瓷复合材料,并对这些复合材料进行了XRD、SEM分析,及其热、力、电性能的测试。结果表明:所制复合材料的热膨胀系数和弯曲强度随着石英含量的增加而增大,其相对介电常数则随之减小。石英质量分数为40%的复合材料在980℃烧结时,析出了大量的方石英相,复合材料的热膨胀系数增大。最终制备的复合材料具有高的热膨胀系数[(10.3～25.5)×10-6/℃]、较高的弯曲强度(146MPa)、较低的相对介电常数(5.6～6.4)及介电损耗(0.10%～0.30%)。

Properties of glass-ceramics with high thermal expansion coefficient

Borosilicates glass(SiO2-BaO-B2O3-Al2O3) and quartz with good dielectric properties and high thermal expansion behavior were selected,a series of glass-ceramic composites were prepared by solid-state method.The phase composition and microstucture of the composites were characterized by X-ray diffraction and scanning electron microscopy.The thermal,mechanic and electric properties of the composites were also measured.The results show that the thermal expansion coefficient and bending strength increase and the relative permittivity decrease when the quartz content is creased.The thermal expansion coefficient is enhanced by the formation of cristobalite during the sintering process at 980℃ in the composite containing 40%(mass fraction) of quartz.The obtained composites show a high thermal expansion coefficient [(10.3-25.5)×10-6/℃],a higher bending strength(146 MPa),and a lower relative permittivity(5.6-6.4) as well as a low dielectric loss(0.10%-0.30%).