BEHAVIOR OF ULTRAHIGH-TEMPERATURE ZrB2-BASED CERAMICS IN OXIDATION

     
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, Krzhizhanovsky 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