Microstructure and Deformation Behavior of Novel Metal–Ceramic Laminated Composites Ta/Ti3Al(Si)C2–TiC

Abstract

New metal–ceramic laminated composites Ta/Ti₃Al(Si)C₂–TiC were obtained by spark plasma sintering. The samples were synthesized at a temperature of 1250°C and a pressure of 50 MPa for 5 min. For formation of the composites, preceramic paper with a powder filler based on the MAX phase of Ti₃Al(Si)C₂, as well as metal foils made of tantalum, were used. The phase composition, microstructure, and elemental composition were analyzed by X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy, respectively. It was found that as a result of sintering, dense multilayer composites were formed, consisting of tantalum metal layers, ceramic layers containing Ti₃Al(Si)C₂, TiC, and Al₂O₃ phases, as well as reaction layers ~13 μm thick at the metal–ceramic interface enriched with Ta, Al, and Si. Based on the mechanical test data, the ultimate bending strength of the obtained composites was determined (σ_bs = ~430 MPa). Metal–ceramic laminated composites with a refractory tantalum layer were shown to exhibit a ductile fracture mechanism accompanied by a more than fourfold increase in absolute deformation compared to a Ti₃Al(Si)C₂-based ceramic composite. This is achieved due to deflection, branching of cracks at the metal–ceramic interface, and plastic deformation of tantalum layers.