【摘要】 碳化硅复合陶瓷广泛应用于电子封装、热交换器等领域，但其存在不易烧结，力学强度较低以及热传导能力不足等问题。考虑到稀土金属氧化物对复合陶瓷材料烧结行为与显微结构方面的调控作用，本文通过放电等离子烧结制备了碳化硅复合陶瓷，研究了HfO₂、Y₂O₃与Sc₂O₃对材料结构、力学性能与导热性能影响。结果表明，HfO₂通过电场效应反应生成HfC，并促使SiC颗粒接触部位的烧结，为热传导提供有效路径。进一步复合引入Y₂O₃与Sc₂O₃，反应生成Y₂Si₂O₇在烧结温度下以液相存在于SiC晶间，提高了材料的致密性，增加了力学强度；与HfO₂协同促进SiC晶粒生长，减少界面热阻，改善了材料的导热性能，制备得到热导率为130.5 W/（m·K）、抗弯强度为440.0 MPa的碳化硅复合陶瓷。更多还原

【Abstract】 Silicon carbide（SiC）composite ceramics are widely used in electronic packaging and heat exchanger applications;however,they face challenges such as difficulty in sintering,relatively low mechanical strength,and insufficient thermal conductivity. Considering the role of rare earth metal oxides in regulating the sintering behavior and microstructure of SiC composites,the SiC composite ceramics prepared by spark plasma sintering（SPS）with the introduction of HfO₂ alone,and further composite additions of Y₂ O₃ and Sc₂ O₃ were investigated in this paper. The effects of HfO₂,Y₂O₃,andSadditives on the structure,mechanical properties,and thermal conductivity of SiC composites were studied. The results indicate that HfO₂,through the electric field effect,reacts to form HfC,promoting the sintering at the contact points between SiC particles and providing an effective path for heat transfer. Further introduction of Y₂ O₃ and Sc₂ O₃ leads to the formation of Y₂ Si₂O₇,which exists as a liquid phase at the sintering temperature,filling the intergranular spaces of SiC,thereby increasing its density. This also improves the fracture mode,enhancing the mechanical strength of the material. Together with HfO₂,these additives promote SiC grain growth,reduce the interfacial thermal resistance,and enhance the thermal conductivity of the material. The resulting SiC composite ceramic exhibits a thermal conductivity of 130.5 W/（m·K）and a flexural strength of 440.0 MPa.更多还原