Microstructure and Mechanical Properties of Alumina Composites with Addition of Structurally Modified 2D Ti3C2 (MXene) Phase

Abstract

This study presents new findings related to the incorporation of MXene phases into ceramic. Aluminium oxide and synthesised Ti3C2 were utilised as starting materials. Knowing the tendency of MXenes to oxidation and degradation, particularly at higher temperatures, structural modifications were proposed. They consisted of creating the metallic layer on the Ti3C2, by sputtering the titanium or molybdenum. To prepare the composites, powder metallurgy and spark plasma sintering (SPS) techniques were adopted. In order to evaluate the effectiveness of the applied modifications, the emphasis of the research was placed on microstructural analysis. In addition, the mechanical properties of the obtained sinters were examined. Observations revealed significant changes in the MXenes degradation process, from porous areas with TiC particles (for unmodified Ti3C2), to in situ creation of graphitic carbon (in the case of Ti3C2-Ti/Mo). Moreover, the fracture changed from purely intergranular to cracking with high participation of transgranular mode, analogously. In addition, the results obtained showed an improvement in the mechanical properties for composites with Ti/Mo modifications (an increase of 10% and 15% in hardness and fracture toughness respectively, for specimens with 0.5 wt.% Ti3C2-Mo). For unmodified Ti3C2, enormously cracked areas with spatters emerged during tests, making the measurements impossible to perform.

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

“…During heating, the titanium oxide, formed as a result of decomposition of Ti 3 C 2 T x , reacted with carbon to form in situ particles of TiC. An interesting experiment was described in work [33]. The authors compared the influence of the Ti 3 C 2 MXene phase and the Ti 3 C 2 phase sputter-coated with high-melting metals (titanium and molybdenum) on the microstructure and mechanical properties of alumina.…”

2D transition metal carbides (MXenes) in metal and ceramic matrix composites

“…The mixture was sintered via SPS at 1400 °C with uniaxial pressure of 35 MPa and a dwell time of 3 min. The resulting CMCs with 0.5 wt% of Ti 3 C 2 T x exhibited an improved hardness (10 %) and fracture toughness (15 %) in comparison to monolithic alumina [59]. High-temperature (1400 ºC) composite sintering turned Ti 3 C 2 T x to TiC particles (Fig.…”

“…There are methods to mitigate MXene oxidation in ceramic oxide matrices. Recently, sputtered multilayer MXene particles with Mo and Ti have been investigated for incorporation into alumina matrices [59]. Sputtering MXene particles with transition metals was used to create a protective shield to prevent oxidation of MXene in the oxide matrix.…”

“…However, sintered composites with Mo-sputtered MXene particles show Mo 2 C at the grain boundaries indicating the reaction of Mo with graphitic carbon during the sintering process. Overall, sputtering MXenes with transition metals was shown to be an effective method to improve the oxidation resistance of MXenes specially when incorporated in oxygenrich matrices and improve the mechanical properties [59]. Further studies are needed to fully understand the effects of the metallic sputtering at the interfacial regimes between metal-MXene, metal-oxide matrices and MXene-oxide matrices.…”

Special Issue: New Findings of MXenes: Preparation, Properties and Applications in Biotechnology and Catalysis

“…Further work of Tomasz Cygan et al [13], entitled "Microstructure and Mechanical Properties of Alumina Composites with Addition of Structurally Modified 2D Ti3C2 (MXene) Phase", concentrates on structural modifications of MXene to harness its oxidation and degradation, particularly at higher temperatures. This is achieved by creating the metallic layer on the Ti3C2Tx, by sputtering the titanium or molybdenum.…”