The production of advanced materials for many branches of the economy takes place with particular emphasis on interfacial reactions [1]. Many concern phenomena occur between solids and liquid metals at high temperatures [2]. The technological processes of producing metal matrix composites (MMCs) are conditioned by obtaining the relevant connection at the reinforcing phase-matrix boundary [3]. Therefore, it is necessary to control the interaction of metals in the liquid state with ceramics to ensure good product quality and, thus, the reliability of their functioning under operating conditions [4]. Literature data indicate that the wear resistance of commercial monolithic iron alloys can be significantly increased by introducing hard ceramic particles into the metal matrix [5]. The most popular ceramic materials used to reinforce iron alloys, i.e. cast iron and cast steel, are oxides and carbides, including Al₂O₃, ZrO₂, B4_C, WC, VC and TiC [6]. Hence, this study presents results of high-temperature wettability for different reinforcements. All experiments were carried out for ferrous alloys. Obtained results indicate significant differences in manufacturing MMCs by ex-situ and in-situ methods. High-temperature interaction between molten gray cast iron and Ti+Cgr substrates was investigated by a sessile drop method combined with non-contact heating of a couple of materials to the test temperature of 1330^oC in an inert gas atmosphere (argon). During high-temperature testing, the images of the couple were recorded by a high-speed, high-resolution CDD camera and used to estimate contact angle values vs time. The analysis of wettability kinetics of different Ti+Cgr substrates by molten cast iron and detailed structural characterisation of solidified couples with the help of light microscopy, electron microscopy, X-ray diffraction and energy dispersive X-ray spectroscopy allowed to explain the mechanism of high-temperature interaction in the selected couples. It was evidenced that good wetting and fast infiltration of all examined substrates with selected alloy have a reactive nature due to the reactively formed wettable TiC phase. These high-temperature phenomena contribute to the formation of three metal-infiltrated zones with different amounts and distribution of TiC particles in cast iron matrix. The obtained results made it possible to illustrate the course of the titanium carbide synthesis reaction considering the intermediate chemical reactions in the Fe-Ti-C ternary system. For comparison, the same analysis was performed under the same testing conditions with oxide-based substrates (Al₂O₃, ZrO₂). The results are discussed regarding specific and principal differences between ex-situ and in-situ routes used to synthesise Fe-based metal matrix composites by liquid-assisted processes. The lack of wettability between oxide ceramics and iron-based alloys was confirmed.

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