Joining of copper alloys (BC6) on spheroidal graphite cast iron (FCD) is effective to enhance the wear resistance of sliding parts. By applying combustion synthesis to a joining to FCD and BC6 has possibilities to enable the process at a lower temperature or for a shorter time. In this study, we examined the application of this process as joining of FCD and BC6 by using Ni–Al–Si compact as filler. Then the effects of the interface microstructure on joining were examined. As a substrate, FCD and BC6 cut into a column of 10.5 ×3 mm were prepared. Ni, Al and Si powders were mixed in the composition of Ni–28?at.%(Al–8?at.%Si), or Ni–78?at.%(Al–8?at.%Si). These powders were die-pressed with a load of 400 MPa for 60 s to the disc shape compact of 10 mm in diameter and 0.5 mm or 0.25 mm in thickness. Dense Ni–Al–Si intermetallic compound coating layer was formed by the combustion synthesis from the elemental mixture of Ni, Al and Si, and was simultaneously bonded with the FCD and BC6 substrate. The composition of the filler was Ni3Al, Al3Ni2 and Ni solid solution. Unreacted Ni was almost consumed by the reaction with Al–Si. Densification was achieved in the interface between filler and substrate as well as in the filler due to molten Al–Si in the filler during hot pressing infiltrates well into the interface between filler and substrates and the boundary of each powder. Reaction layer of Ni–Al–Cu was formed in the interface between filler and BC6 achieving chemically bonding.
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