Influence of Ti3C2Tx MXene and Surface-Modified Ti3C2Tx MXene Addition on Microstructure and Mechanical Properties of Silicon Carbide Composites Sintered via Spark Plasma Sintering Method

Abstract

This article presents new findings related to the problem of the introduction of MXene phases into the silicon carbide matrix. The addition of MXene phases, as shown by the latest research, can significantly improve the mechanical properties of silicon carbide, including fracture toughness. Low fracture toughness is one of the main disadvantages that significantly limit its use. As a part of the experiment, two series of composites were produced with the addition of 2D-Ti3C2Tx MXene and 2D-Ti3C2Tx surface-modified MXene with the use of the sol-gel method with a mixture of Y2O3/Al2O3 oxides. The composites were obtained with the powder metallurgy technique and sintered with the Spark Plasma Sintering method at 1900 °C. The effect adding MXene phases had on the mechanical properties and microstructure of the produced sinters was investigated. Moreover, the influence of the performed surface modification on changes in the properties of the produced composites was determined. The analysis of the obtained results showed that during sintering, the MXene phases oxidize with the formation of carbon flakes playing the role of reinforcement. The influence of the Y2O3/Al2O3 layer on the structure of carbon flakes and the higher quality of the interface was also demonstrated. This was reflected in the higher mechanical properties of composites with the addition of modified Ti3C2Tx. Composites with 1 wt.% addition of Ti3C2Tx M are characterized with a fracture toughness of 5 MPa × m0.5, which is over 50% higher than in the case of the reference sample and over 15% higher than for the composite with 2.5 wt.% addition of Ti3C2Tx, which showed the highest fracture toughness in this series.

Investigation of MXenes Oxidation Process during SPS Method Annealing

“…The presence of porous particles, with a shape similar to MXene, proves the formation of the disordered carbon structures described in our previous papers [16]. However, the morphology of these particles differs from those we observed in the SiC matrix sinters [16,17]. Because the observations of the MXene powders after the annealing process did not show the presence of disordered carbon structures, similar tests were carried out for the SiC-C-B-Ti3C2 powder mixtures.…”

“…The presence of porous particles, with a shape similar to MXene, proves the formation of the disordered carbon structures described in our previous papers [16]. However, the morphology of these particles differs from those we observed in the SiC matrix sinters [16,17]. The disordered carbon structure particles did not show such porosity.…”

“…The formation of carbon structures and their presence at such a high temperature are explained by the composition of the sintered SiC-C-B powder mixtures. The absence of oxide additives and sintering in a vacuum results in only a small amount of oxygen (adsorbed on the MXene surface) which favors the formation of carbon structures [17]. This can be confirmed by works describing the SPS sintering of composites on oxide matrices or with oxide additives, where MXene decomposes completely during the sintering process [18,19].…”

MXenes—A New Class of Two-Dimensional Materials: Structure, Properties and Potential Applications

“…The ZnO-Ti 3 C 2 composite produced by the cold sintering process improved the electrical conductivity of the oxide matrix by 1-2 orders of magnitude and showed a 150% increase in hardness and elastic modulus [122]. The enhancement of mechanical properties of silicon carbide modified with Ti 3 C 2 T x was also reported by Petrus et al [123]. The Ti 3 C 2 T x MXene composite films with segregated polystyrene inclusions studied by Iqbal et al [124] showed superior electromagnetic interference efficiency, making them a promising shielding material with tunable electromagnetic wave absorption properties.…”

MXene-Based Ceramic Nanocomposites Enabled by Pressure-Assisted Sintering

“…Coupled with their many advantageous properties, the 2D nature of MXenes makes them ideal candidates for fillers or reinforcement in composite materials. Thus far, research on MXene-based composites or hybrids has been primarily focused on 2D freestanding, colloidal, or film nanocomposites. − Due to the simplicity of incorporating MXenes into polymers, numerous studies have demonstrated the promise of bulk MXene-based polymers composites, and extensive reviews have been published. − In contrast, relatively few studies have considered bulk nanocomposites based on MXenes incorporated in metallic − or ceramic − matrices, despite the vast potential of such 2D-integrated metal matrix composites (MMC) and ceramic matrix composites (CMC). − This disparity undoubtedly stems from the primary challenges of producing bulk MXene-based composite materials requiring high-temperature processing. These challenges include achieving dense samples with a homogeneous distribution of the MXene, retaining the MXene phase and 2D structure, and preventing adverse chemical reactions between MXene and the surrounding matrix.…”