Ultra-refractory ceramics: the use of sintering aids to obtain microstructure control and properties improvement

被引：16

作者：

Bellosi, A ^{[1
]}

Monteverde, F ^{[1
]}

机构：

[1] CNR, ISTEC, I-48018 Faenza, Italy

来源：

EURO CERAMICS VIII, PTS 1-3 | 2004年 / 264-268卷

关键词：

UHTC; zirconium diboride; hafnium diboride; silicon carbide; ceramic composites; sintering; microstructure; mechanical properties; oxidation resistance;

D O I：

10.4028/www.scientific.net/KEM.264-268.787

中图分类号：

TQ174 [陶瓷工业]; TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The present study focuses on innovative processing for the densification of refractory diborides (ZrB2, HfB2) based ceramics, suitable to fabricate UHTC components for structural applications and thermal protection systems. The addition of small quantities (2-5 vol%) of sintering aids allows to overcome the intrinsic low sinterability of zirconium diboride and to improve properties through the microstructural refinement. The introduction of second refractory phases, for instance 20 vol% of SiC in the diboride matrices improves strength, toughness and oxidation resistance. Outstanding properties were measured: fracture toughness 3-5 MPam(1/2), hardness 9-20 GPa, elastic modulus 350-420 GPa, flexural strength 300 to 750 MPa at R.T and up to 300 MPa at 1500degreesC. The resistance to oxidation of different materials was compared.

引用

页码：787 / 792

页数：6

共 16 条

[1] Microstructure and properties of ZrB2-based ceramics [J].