High strength hollow ceramic spheres are incorporated into epoxy resin to prepare insulating composite materials. The characterization shows simultaneous enhancement in thermal conductivity, mechanical strength and dielectric permittivity. A thermal conductivity of 1.36 W/(m·K) (7.5 times of that of pure epoxy) is measured from the sample prepared from hollow spheres with high alumina content. The compressive strength and impact strength measured from the same sample are 104.04 MPa and 3.61 kJ/m2, corresponding to an increase of 18.3 and 31.4 %, respectively, from pure epoxy. The permittivity of the sample measured at low frequency is 9.85 which decreases slightly as frequency increased to 106 Hz. The electrical breakdown data are analyzed with Weibull model and the decreased breakdown strength is explained.

中文翻译：

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空心陶瓷球-环氧介电复合材料的制备及性能

将高强度空心陶瓷球掺入环氧树脂中制备绝缘复合材料。表征显示热导率、机械强度和介电常数同时增强。由氧化铝含量高的空心球制备的样品测得的热导率为 1.36 W/(m·K)（纯环氧树脂的 7.5 倍）。从同一样品测得的压缩强度和冲击强度分别为 104.04 MPa 和 3.61 kJ/m2，分别对应于纯环氧树脂的 18.3% 和 31.4% 的增加。在低频下测得的样品介电常数为 9.85，随着频率增加到 106 Hz，该介电常数略有下降。用威布尔模型分析电击穿数据，解释击穿强度降低。