添加β-Si_3N_4棒晶对氮化硅陶瓷力学性能的影响  

Effects of Seeding with β-Si_3N4 Rod Crystals on Mechanical Properties of Silicon Nitride Ceramics

作　　者：陈殿营[1] 张宝林[1] 庄汉锐[1] 李文兰[1] 

机构地区：[1]中国科学院上海硅酸盐研究所,上海200050

出　　处：《无机材料学报》2003年第5期1139-1142,共4页Journal of Inorganic Materials

基　　金：中国科学院上海硅酸盐研究所创新基金

摘　　要：将由自蔓延燃烧合成法制备的β—Si3N4棒晶加入到α-Si3N4起始原料中,研究了热压烧结氮化硅陶瓷力学性能的变化.随棒晶添加量的增加,材料的韧性提高,抗弯曲强度下降.与不加棒晶相比,加入8wt％的β-Si3N4棒晶可使陶瓷的韧性从4.0MPa·m1/2提高到6.7MPa·m1/2.断口形貌和压痕裂纹的显微结构观察表明,韧性的提高源于长柱状晶粒的拔出和裂纹的偏转.In this paper, the effects of seeding β-Si3N4 rod crystals prepared by self-propagating high-temperature synthesis on the mechanical properties of silicon nitride ceramic were investigated. The experimental results showed that with the increase of β-Si3N4 rod crystals content, the fracture toughness increases, while the flexile strength decreases. The fracture toughness can increase from 4.0MPa·m1/2 to 6.7MPa·m1/2 when 8wt%·-Si3N4 rod crystal was added compared with that without seeding. The improvement of fracture toughness results from the grain pullout and bridging, branching of elongated grains.

关 键 词：β—Si3N4棒晶 氮化硅 断裂韧性 

分 类 号：TQ174[化学工程—陶瓷工业]