In situ synthesis mechanism of ZrC‐ZrB2/Cu composites prepared by SHS‐casting method

The self‐propogating high‐temperature syntheis (SHS) experiments in the glove box indicated that the combustion temperature decreased and the ignition time increased with increasing B4C size in Cu‐Zr‐B4C system. Once B4C size exceeded 28 μm, the full conversion of ZrC and ZrB2 failed. In situ ZrC and ZrB2 ceramic particle‐reinforced Cu matrix composites were produced by the self‐propagating high‐temperature synthesis reaction of Cu‐Zr‐B4C system in molten Cu. Moreover, the phase formation mechanism was investigated by the combustion wave quenching experiment of Cu‐Zr‐B4C powder compact in Cu liquid. Results showed that ZrC and ZrB2 were mainly formed by the dissolution‐reaction‐precipitation mechanism. A developed method arresting the combustion front of a reactant in molten metal was proposed.