Fabrication and characterization of highly thermal conductive Si3N4/diamond composite materials

• Published in: Materials & design Vol. 225; p. 111482
• Main Authors: Wu, Dandan, Wang, Chengyong, Hu, Xiaoyue, Chen, Wanglin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.01.2023; Elsevier
• Subjects: Chemical bonding interface; Diamond particle; Multilayer structure; Silicon nitride; Thermal conductivity; Thermal conductivity; Diamond particle; Chemical bonding interface; Multilayer structure; Silicon nitride
• ISSN: 0264-1275; 1873-4197
• DOI: 10.1016/j.matdes.2022.111482

[Display omitted] •High-thermal-conductivity composites with silicon nitride (Si3N4) as the matrix and diamond particles as the reinforcing phase were successfully developed.•Si3N4/diamond composites offered maximum thermal conductivity of 201.96 W·m−1·K−1, an increase of 272.87 % compared with Si3N4.•The composites exhibited high hardness (32.84 GPa) and low coefficient of thermal expansion (3.07 × 10-6/K).•The titanium carbonitride formed at the interface created a chemical bonding and inhibited the graphitization of diamond (approximately 100 nm).•Multilayered designs endowed composites with directional heat transfer feature, and the anisotropy increased by 66.67% compared with non-multilayer structure. A novel composite materials using silicon nitride (Si3N4) as the substrate and diamond particles as the reinforcement phase were developed to increase both thermal conductivity and mechanical properties. The Ti coating on the surfaces of the diamond particles facilitated the formation of a titanium carbonitride (TiCiN1-i) interface between the two constituents during sintering, creating a strong bonding for high thermal conduction at the diamond-Si3N4 interface and inhibiting the graphitization of diamond during the sintering process. Furthermore, a sandwiched material design was made whereby Si3N4 and Si3N4/Ti-coated diamond layers were stacked alternately to endow the composites with a directional heat conduction characteristic. The thermal conductivity of the fabricated Si3N4/diamond composites increased by up to 272.87 % compared to that of commercially available Si3N4, making them excellent candidates for thermal management materials required in high-performance electronic devices.