Production of Ti3SiC2-based materials by SHS forced compaction of layered composite Ti–SiC

Abstract

A new method of synthesizing ceramic composite materials based on Ti 3 SiC 2 using non-powder reaction compositions of titanium and silicon carbide was developed. A ceramic composite with a Ti 3 SiC 2 -TiSi 2 matrix reinforced with SiC particles was obtained by SHS forced compaction of a multilayer packet of regularly packed layers of titanium foil and polymer film filled with silicon carbide particles. The particulars of the phase composition and microstructure of the material obtained were investigated.The innovational potential of Ti 3 SiC 2 -based ceramic materials is due to their unique combination of properties: high resistance to cracking, insensitivity to thermal shock, and good mechanical workability. These properties are mainly due to layered character of the Ti 3 SiC 2 crystalline structure, expressed as a relatively weak bond between carbide layers [Ti 3 C 2 ] ¥¥ and the layers of silicon atoms [Si] ¥¥ separating them. Such a nano-laminated structure makes it possible for Ti 3 SiC 2 grains to deform strongly under a load, localizing the mechanical damage to the material thereby preventing macroscopic fracture [1]. A diagram of the crystalline structure of Ti 3 SiC 2 and the microstructure of its grains is presented in Fig. 1.The high cost and technical complexity of the existing methods of production is holding back the adoption of Ti 3 SiC 2 -based materials in industry: hot isostatic pressing [2 -5], spark plasma sintering [6,7], chemical precipitation from the gas phase [8,9], and so on. Finding technologically efficient and cost-effective methods of production is among the most pressing problems at the present stage of research. A promising approach to solving this problem could be the application of self-propagating high-temperature synthesis (SHS) using layered reaction compositions consisting of a packet of regularly packed reagents in the form of films and foils. For the production of large articles such a technology greatly simplifies the procedure for forming articles, which gives tangible advantages over powder methods,.This article presents the results of laboratory experiments on obtaining Ti 3 SiC 2 -TiSi 2 -SiC ceramics by SHS forced compaction of layered reaction composition Ti-SiC.

Physico-chemical and mechanical properties of Ti3SiC2-based materials elaborated from SiC/Ti by reactive spark plasma sintering

“…A recent study, using titanium foils and polymer films highly filled with micro-sized SiC as starting materials [13], showed that the composition's result was quite close to our obtained material at a sintering temperature of 1400 ℃. The material was synthesized by SHS process and consisted of 72, 14, and 13 wt% of Ti 3 SiC 2 , SiC, and TiSi 2 , respectively, as well as traces of TiC and Ti 5 Si 3 C x .…”

“…However, regardless of the sintering temperature, the relative density increased with the increase of the holding time and became, for instance, higher than 99.9% for 20 min of holding time under a pressure of 60 MPa. According to the study of Istomin et al [13], the relative density of the material synthesized by SHS process, subjected to vacuum heat-treatment under a mechanical load 0.2 MPa, does not exceed 80%, whereas with the SPS technique, a high density close to the theoretical density, can often be achieved. The relationship between relative density of the material and the crystallite size of Ti 3 SiC 2 is represented by Fig.…”

“…Among these mixtures, we quote Ti/Si/C [5], Ti/C/SiC [6], Ti/SiC [7], and Si/TiC [8]. Several researchers reported on the synthesis of Ti 3 SiC 2 starting from Ti/SiC in fine powder or nonpowder forms such as films, foils, and rods by using different processes [9][10][11][12][13][14]. These sintering processes were often performed at relatively high temperature (more than 1400 ℃) for a long time.…”