Effects of matrix grain size on the mechanical properties of Si3N(4)/SiC nanocomposites densified with Y2O3

被引：20

作者：

Hirano, T ^{[1
]}

Ohji, T ^{[1
]}

Niihara, K ^{[1
]}

机构：

[1] NATL IND RES INST NAGOYA, NAGOYA, AICHI 462, JAPAN

来源：

MATERIALS LETTERS | 1996年 / 27卷 / 1-2期

关键词：

Si3N4; SiC; nanocomposites; grain size; aspect ratio; mechanical properties; creep behavior;

D O I：

10.1016/0167-577X(95)00248-0

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Effects of matrix grain size on the room-temperature mechanical properties and high-temperature creep behavior were investigated for Si3N4/30 vol% SiC nanocomposites. The nanocomposites with different matrix grain sizes were fabricated by hot-pressing the mixtures of nano-sized beta-SiC (40 nm) and alpha-Si3N4 (200 nm) powders. 8 wt% of Y2O3 was used as an sintering aid. With increasing the hot pressing time, the alpha-beta transformation and grain growth of rod-like beta-Si3N4 were promoted and the number of equiaxed grains decreased. The fracture strength and toughness were improved and the creep rate at 1400 degrees C and 200 MPa decreased. The observed improvement of mechanical properties and creep resistance was rationalized by the microstructural changes.

引用

页码：53 / 58

页数：6

共 25 条

[1] ELEVATED-TEMPERATURE-DELAYED FAILURE OF ALUMINA REINFORCED WITH 20 VOL-PERCENT SILICON-CARBIDE WHISKERS [J].