Joining of Ti3SiC2 by Magnetron Sputtering a Layer of Cu or Zr Followed by Heat Treating at Relatively Low Temperatures

Ti3SiC2 joining has been successfully achieved by depositing a thin Cu or Zr layer on it and heat treating at low temperatures of 950 degrees or 1100 degrees C in an argon atmosphere, respectively, which are similar to 500 degrees C lower than the previous solid solution joining method. X-ray diffraction and scanning electron microscope analyses reveal that a continuous Cu3Si or Zr-silicide layer forms at the joint interface through the outward diffusion of Si atoms from the Ti3SiC2 substrate into the deposited Cu or Zr layer. The strength of joints is evaluated by tensile bond-strength test and 4-point bending test methods. The Ti3SiC2/Cu/Ti3SiC2 joints always fail from the substrate instead of from the bonding interface, while the Ti3SiC2/Zr/Ti3SiC2 joints fail from the joint interface during tensile bond-strength test. The 4-point bending strength of Ti3SiC2/Cu/Ti3SiC2 joints reaches a value of 238 MPa, which is 68% of the Ti3SiC2 substrate. So joining using a Cu or Zr film as the interlayer followed by heat treating is a practical and efficient method for joining Ti3SiC2.