Microstructural characterization of GPSed-RBSN and GPSed-Si3N4 ceramics

被引：17

作者：

Lee, BT

Yoo, JH

Kim, HD

机构：

[1] Kongju Natl Univ, Div Adv Mat Engn, Kongju 314701, South Korea

[2] Korea Inst Machinery & Mat, Ceram Mat Grp, Changwon 641010, South Korea

来源：

MATERIALS TRANSACTIONS JIM | 2000年 / 41卷 / 02期

关键词：

microstructure; gas-pressure-sintering; reaction-bonded silicon nitride; fracture toughening mechanism;

D O I：

10.2320/matertrans1989.41.312

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Microstructural characterization of gas-pressure-sintered reaction-bonded Si3N4 (GPSed RBSN) and gas pressure-sintered Si3N4 (GPSed Si3N4) ceramics at 2223 K far 12.6 ks has been investigated using by back-scattered SEM, TEM and XRD. No residual Si phase was observed in reaction bonded body nitrided at 1673 K for 72 ks, but many residual pores with about 3 mu m was observed. Most of Si3N4 grain boundaries and triple points in both GPSed bodies were covered with amorphous phases. The aspect ratio of large rod-like Si3N4 grains in GPSed Si3N4 was about 10, which was larger than that in GPSed RBSN body. The main fracture mode in both sintered bodies was intergranular fracture with rough surfaces. The values of fracture toughness and fracture strength in both samples were 7.8 MPa.m(1/2), 731 MPa and. 8.0 MPa.m(1/2). 632 MPa, respectively.

引用

页码：312 / 316

页数：5

共 17 条

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[2]

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