Phase Interaction between ZrB2–SiC Composite Ceramics with Oxide Melts

 
A.Panasyuk,
  
T.Dubovik
 

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, 2012, #09/10
http://www.materials.kiev.ua/article/1090

Abstract

The paper studies the mechanism of interaction between the ZrB2–ZrSi2–SiC composites and dross-type oxide melts formed during the combustion of low-reactive carbons containing oxide rocks up to 30–40 vol.%. It is established that the silicon carbide from the surface layer of the composite interacts with the iron oxides to form spherical deposits of the FeSix phase at 1350–1550 °С in the wetting process and in contact with the dross during 10–50 h. In the composite–dross contact area, a thin (~7.5–30.0 μm) layer of ZrО2 and SiО2 oxides is formed (depending on the amount of SiC and ZrSi2), the latter serving as a protective film, preventing the composite ceramics from corrosion in the oxide melts. The optimum composition of the ZrB2–ZrSi2–SiC ceramics which can be used as corrosion-resistant in the oxide melts is determined.


CONTACT INTERACTION, IRON SILICIDE, LOW-REACTIVE CARBONS, SPHERICAL DEPOSITS, ZRB2–ZRSI2–SIC COMPOSITE CERAMICS