BN/La-Al-Si-O composite ceramics were fabricated by hot-pressed sintering using hexagonal boron nitride (h-BN), lanthanum oxide (La₂O₃), aluminia (Al₂O₃), and amorphous silica (SiO₂) as the raw materials. The effects of sintering temperature on microstructural evolution, bulk density, apparent porosity, and mechanical properties of the h-BN composite ceramics were investigated. The results indicated that La-Al-Si-O liquid phase was formed during sintering process, which provided an environment for the growth of h-BN grains. With increasing sintering temperature, the cristobalite phase precipitation and h-BN grain growth occurred at the same time, which had a significant influence on the densification and mechanical properties of h-BN composite ceramics. The best mechanical properties of BN/La-Al-Si-O composite ceramics were obtained under the sintering temperature of 1700 °C. The elastic modulus, flexural strength, and fracture toughness were 80.5 GPa, 266.4 MPa, and 3.25 MPa·m^1/2, respectively.

BN / La-Al-Si-O复合陶瓷是通过六方氮化硼（h-BN），氧化镧（La ₂ O ₃），氧化铝（Al ₂ O ₃）和无定形二氧化硅（SiO）进行热压烧结制成的_2个）作为原料。研究了烧结温度对h-BN复合陶瓷显微组织演变，堆积密度，表观孔隙率和力学性能的影响。结果表明，在烧结过程中形成了La-Al-Si-O液相，为h-BN晶粒的生长提供了环境。随着烧结温度的升高，方石英相的析出和h-BN晶粒的生长同时发生，这对h-BN复合陶瓷的致密化和力学性能产生了重要影响。在1700°C的烧结温度下获得了BN / La-Al-Si-O复合陶瓷的最佳机械性能。弹性模量，弯曲强度和断裂韧性分别为80.5 GPa，266.4 MPa和3.25 MPa·m ^1/2， 分别。