High Toughness Laminated Composites Fabricated from Ti₃Al(Si)C₂ Filled Preceramic Paper and Nb Foils: Formation Mechanism and Influence of Laminate Architecture

In this work high strength and tough metal‐ceramic laminated composites are fabricated by spark plasma sintering (SPS) of Ti₃Al(Si)C₂ MAX‐phase filled preceramic papers (TAC) and ductile Nb foils. The sintering is carried out at 1250 °C and 50 MPa for 5–20 min. Various stacking techniques are used to obtain Nb/TAC laminated composites with different architectures. SPS results in the formation of reaction layer (RL) with a complex composition, which changes the thickness insignificantly with increasing sintering time. The possible formation mechanism of RL is discussed. The bending strength of Nb/TAC composites is decreased from 410 to 350 MPa when lowering the thickness of ceramic layer. The maximum fracture toughness of 10.2 MPa·m^1/2 is achieved for the composite with similar individual layers thickness. The toughening is explained by complex fracture mechanisms associated with deflection and branching of cracks at interfaces, delamination, plastic deformation of Nb layers, multiple cracking and crack deflection in ceramic TAC layers.