Microstructure and mechanical properties of transient liquid phase bonding Ti₃SiC₂ ceramic to SUS430 steel using an Al interlayer

Ti₃SiC₂ ceramic and SUS430 ferritic stainless steel were welded by the transient liquid phase (TLP) diffusion bonding method using an Al interlayer at 850–1050 °C in vacuum. The evolution of phase and morphology at the interface and bonding strength were systematically investigated. The results show that Ti₃SiC₂ and SUS430 were well bonded at 900–950 °C. Three reaction zones were observed at the interface. At the joint interface area adjacent to alloy, the alloy completely reacted with liquid Al to form Al₈₆Fe₁₄. At Ti₃SiC₂/Al interface, Ti and Si diffused outward from Ti₃SiC₂ into the molten Al to form Fe₃Al + Al₅FeSi + TiAl₃ zone. Adjacent to Ti₃SiC₂ matrix, Ti₃Si(Al)C₂ + TiC_x zone was formed by the loss of Si. The evolution mechanism of TLP-bonded joints was discussed based on the interface microstructure and product phases. In addition, the tensile strength of the joint increased with increasing bonding temperature. The corresponding maximum value of 59.7 MPa was obtained from SUS430/Al (10 μm)/Ti₃SiC₂ joint prepared at 950 °C.