摘要
利用热压的方法制得室温断裂韧性和抗弯强度分别为１１．２ＭＰａ·ｍ￣（１／２）、８２３ＭＰａ，高温（１３５０℃）断裂韧性和抗弯强度分别为２３．９ＭＰａ·ｍ￣（１／２）、６３０ＭＰａ的自韧Ｓｉ＿３Ｎ＿４陶瓷。研究了显微结构和力学性能之间的关系。结果表明：玻璃相的含量、β－Ｓｉ＿３Ｎ＿４的长径比等对性能有重要影响。分析了自韧Ｓｉ＿３Ｎ＿４陶瓷的增韧机理，通过ＳＥＭ明显观察到Ｓｉ＿３Ｎ＿４中存在裂纹偏转、分支和β－Ｓｉ＿３Ｎ＿４拔出现象。
The fracture toughness and flexural strength of in-situ toughened Si_3N_4 ceramic with 11.2 MPa·m￣(1/2),823MPa at room temperature and 23. 9MPa·m￣(1/2), 630MPa at high temperature(1350℃ ) were obtainedby HP methed,respectively. The relation between microstructure and mechanical properties was studied.The result shows that the anlount of glassy phase and the aspect ratio of β-Si_3N_4 have significant effects onthe properties of the material.The toughened mechanism of in-situ toughened Si_3N_4 ceramic was analyzed,and the phenomena of crack deflection,crack branching and β-Si_3N_4's being pulled out were obviousobserved by SEM.
出处
《高技术通讯》
CAS
CSCD
1994年第10期20-22,共3页
Chinese High Technology Letters
基金
国家"八五"预研项目
关键词
显微结构
性能
氮化硅陶瓷
In-situ toughened Si_3N_4,Microstructure,Mechanical properties,Toughened mechanism
