The peculiarities in oxidation behavior of the ZrB2-SiC ceramics with chromium additive

被引：17

作者：

Bannykh, D. ^{[1
,2
]}

Utkin, A. ^{[1
]}

Baklanova, N. ^{[1
]}

机构：

[1] Inst Solid State Chem & Mechanochem SB RAS, 18 Kutateladze St, Novosibirsk 630128, Russia

[2] Novosibirsk State Univ, 1 Pirogova St, Novosibirsk 630090, Russia

来源：

INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS | 2019年 / 84卷

关键词：

Sintering; Thermal properties; Oxidation; Chromium; Borides; Silicon carbide; DENSIFICATION; TEMPERATURE; MICROSTRUCTURE; KINETICS; HFB2;

D O I：

10.1016/j.ijrmhm.2019.105023

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

ZrB2-SiC-Cr powder sintering at 1600 degrees C and its oxidation behavior at 1000-1500 degrees C in air were studied as a function of chromium content. It was shown that the relative density of the ZrB2-SiC ceramics increases with an increase in chromium content in the powdered mixture. This is related to the formation of the liquid Cr-Si-C-B phase during the high-temperature interaction of SiC with chromium and ZrB2. It was stated that the mechanism of ZrB2-SiC-Cr ceramics oxidation is changed from bulk to passive. The oxidation resistance is improved for the ceramics with 13% of chromium or less, which can be explained by a decrease in its porosity. The ceramics with higher chromium content demonstrates the opposite effect, namely, large-size Cr2O3 crystals are formed during oxidation, this promotes microcracking in the oxidizing layer and causes damage of surface integrity. As a result, the oxidation resistance of the ZrB2-SiC-Cr ceramics with high chromium content is decreased.

引用

页数：8

共 22 条

[1] Effect of chromium additive on sintering and oxidation behavior of HfB2-SiC ceramics [J].