Абстрактный

Mechanical and Electromagnetic Properties of Carbon Fiber Toughened Si3N4 Ceramic Composites

Qinggang Li, Yuhang Du, Ning Sun, Jinkai Li, Mengyong Sun, Guopu Shi

Carbon fiber-reinforced Si₃N₄ ceramic materials were prepared by hot pressing sintering process using silicon nitride as substrate and short carbon fiber reinforcement. The mechanical properties, microstructure and electromagnetic properties of the sintered samples were evaluated. Experimental results show that atmosphere hot pressing can reduce the sintering temperature of Si3N4 ceramics and promote phase transition. When the additional amount of carbon fiber is 3.0 wt%, the sintering temperature is 1700°C, the holding time is 30 min, forming pressure is 30 MPa, the sintered sample has the best extensive properties: hardness (>8.5 GPa) and density (>2.8 g/cm³) meet the engineering needs, fracture toughness is enhanced by 22.7%, fracture toughness can reach 8.11 MPa•m^1/2, dielectric properties are also improved.