BEHAVIOR OF ULTRAHIGH-TEMPERATURE ZrB2-BASED CERAMICS IN OXIDATION

    
A.Koroteev,
 
O.V.Buriachek,
 
D.V.Vedel,
 
А.N.Stepanchuk,
 
L.Silvestroni
 

I. M. Frantsevich Institute for Problems of Materials Science of the NAS of Ukraine, Omeliana Pritsaka str.,3, Kyiv, 03142, Ukraine
Powder Metallurgy - Kiev: Frantsevich Institute for Problems of Materials Science NASU, 2017, #09/10
http://www.materials.kiev.ua/article/2436

Abstract

Ultrahigh-temperature ZrB2-based ceramics with different sintering additives for ex-treme conditions were developed. Their strength characteristics, phase composition, and structure were examined. The ceramics were oxidized in air at 1250 and 1550 °C. In addi-tion, the most stable composites were subjected to temperature-cycle test in a flow of aviation fuel combustion products in a temperature range of 1400–1500 °C. All materials have high oxidation resistance. The method used to produce samples influences their oxidation behavior: materials produced by vacuum hot pressing show higher oxidation resistance than those produced by hot pressing in a CO–CO2 atmosphere, probably because of their higher final density. The best results were obtained when ZrB2 was sintered with the simultaneous introduction of MoSi2 and CrB2.


OXIDATION, THERMIC CYCLING, ULTRAHIGH-TEMPERATURE CERAMICS, ZIRCONIUM BORIDE