Wetting benavior and contact interaction in TiB₂—SiC)—(Ni—Mo) system

Abstract

The wettability and interraction of ТiB₂—SiC with melted Ni—Mo alloys have been investigated. The wetting contact angles were determined, the structure and phase composition of the drops have been investigated by the methods of energy dispersive X-ray microanalysis. The wetting tests have shown that addition of 5—25% (wt.) molybdenum into nickel results in the improvement of ТiB₂—SiC wetting with Ni—Mo alloys. However, molybdenum and silicon carbide have shown high chemical activity. Because of Ni—Mo intermetallics and complex titanium—molybdenum borides formation, the metallic phase became poor one as to molybdenum content that leads to active interaction of nickel with silicon and formation of nickel silicides. Besides, formation of Nibased solid solution of silicon and titanium was detected in the drop zones. The formation of new chemical compounds leads to the brittleness of metal alloy. Thus, (ТiB₂—SiC)—(Ni—Мо) system is not recommended to design new composite materials.