氧化铝颗粒大小对氧化铝玻璃复合体力学性能的影响

Effects of Alumina Particle size on Mechanical Properties of Alumina glass Composite

目的：研究氧化铝颗粒大小对氧化铝玻璃复合体力学性能的影响。方法：采用两种不同大小颗粒的氧化铝原料，经等静压成型，１４００℃２小时的低温烧结，制作了部分烧结的多孔氧化铝，经镧硼硅玻璃渗透形成了氧化铝玻璃复合体。结果：用纳米颗粒氧化铝制作的氧化铝玻璃复合体强度（３５８．２ＭＰａ）、断裂韧性（２．３８ＭＰａｍ１／２）显著低于微米氧化铝玻璃复合体的强度（４３２．２ＭＰａ）和断裂韧性（５．１２ＭＰａｍ１／２）。ＳＥＭ显示纳米氧化铝玻璃复合体中气孔率占１１．５％，玻璃相成分多；微米氧化铝玻璃复合体中气孔率仅占１．２％。玻璃相成分少。结论：氧化铝玻璃复合体中氧化铝的体积百分数和气孔率对其强度和断裂韧性起着关键性作用。

Objective:To study the effects of alumina particle size on mechanical properties of alumina glass composite. Methods: Alumina compacts were prepared by isostatic press method and sintered at 1400℃ for 2 hours with two various particle size alumina. Alumina glass composite was made by infiltrating partially sintered porous alumina with glass at 1200℃ for 4 hours.Results:The strength and fracture toughness of nanometre alumina glass composite were 358 2 MPa, 2 38 MPam 1/2 respectively. The strength and fracture toughness of micrometer alumina glass composite were 432 2 MPa, 5 12 MPam 1/2 respectively. Image analysis of SEM micrograph showed that porous rate was about 11 5% in the nanometer alumina glass composite, 1 2% in the micrometer alumina glass composite, and there was more glass composition in the nanometer alumina glass composite than that in the micrometer alumina glass composite.Conclusion: The alumina volume percentage and porous rate play an important role in the strength and fracture toughness of alumina glass composite.