Development of Hybrid-Type Ceramic Matrix Composites Based on Fail-Safe Concept

基于故障安全概念的混合型陶瓷基复合材料的开发

基本信息

批准号：
05302049
负责人：
KISHI Teruo
金额：
$ 14.02万
依托单位：
The University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Co-operative Research (A)
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1995
项目状态：
已结题

项目摘要

Fracture toughness of high-strength ceramics can be improved through the microstructure control and composite reinforcement. Nano-size-particle-dispersed composites are most promising among other candidate materials. The following three types of alumina based hybrid-type nano-composites were investigated through this study, in order to demonstrate the fundamental mechanism of nano-size intragranular dispersion and the contollability of the micructure by intergranular dispersion.(1) Al_2O_3/5vol% Nano-Size SiC Dispersed Composites : Although very small SiC particles tended to exist within alumina grains, larger ones are dispersed at grain boundaries. The dispersion process of nano-size particles was closely related with the degree of alumina matrix densification. The grain size of alumina could be contolled by carefully selecting the size of reinforcing particles.Both strength and toughness were improved through nano-size particle dispesion.(2) Al_2O_3/SiC/YAG Hybrid Composites : Micron-size YAG and nano-size SiC particles were successfully dispersed to fabricate Al_2O_3/SiC/YAG Hybrid Composites. Since the grain growth of alumina was controlled and homogeneous microstrucure was accomplished, the mechanical properties were much improved through hybritization.(2) Al_2O_3/LaAl_<11>O_<18> Composites : Alumina matrix composites with elongated fiber-like reinforcing phases were sucessfully fabricated. Both strength and fracture toughness increased as the volume fraction increased. In particular, the fracture toughness was much improved through the increase in the aspect ratio of reinforcement. Bridging and crack deflection contributed the toughness improvement to a large extent.

可以通过微结构控制和复合加固来改善高强度陶瓷的断裂韧性。在其他候选材料中，纳米大小颗粒分散的复合材料是最有前途的。 The following three types of alumina based hybrid-type nano-composites were investigated through this study, in order to demonstrate the fundamental mechanism of nano-size intragranular dispersion and the contollability of the micructure by intergranular dispersion.(1) Al_2O_3/5vol% Nano-Size SiC Dispersed Composites : Although very small SiC particles tended to exist within alumina谷物，较大的谷物分散在晶界。纳米大小颗粒的分散过程与氧化铝基质致密化程度密切相关。 The grain size of alumina could be contolled by carefully selecting the size of reinforcing particles.Both strength and toughness were improved through nano-size particle dispesion.(2) Al_2O_3/SiC/YAG Hybrid Composites : Micron-size YAG and nano-size SiC particles were successfully dispersed to fabricate Al_2O_3/SiC/YAG Hybrid Composites.由于控制了氧化铝的谷物生长并完成了均匀的微观疗法，因此通过杂交通过杂交大大改善了机械性能。（2）Al_2o_3/laal_ <11> O_ <11> O_ <11> O_ <18>复合材料：氧化铝基质复合材料，具有带状纤维的强化阶段的氧化铝矩阵复合材料。随着体积分数的增加，强度和断裂韧性都会增加。特别是，通过增强纵横比的增加，裂缝韧性得到了很大改善。桥接和裂纹挠度在很大程度上促进了韧性的改善。