Preparation and characterization of copper matrix composites by reaction sintering of the Cu–Mg–B system

Mg–B intermetallics reinforced copper matrix composites were prepared by reaction sintering of the Cu–Mg–B system. The sintering was performed at the temperature as determined from the result of the differential thermal analysis (DTA). The phases formed in the samples were identified by X-ray diffraction (XRD). The microstructures were observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). These results indicate that some Mg–B intermetallic involving MgB2, MgB4 and MgB6 were produced in the copper matrix. The interface between the in situ formed Mg–B intermetallic particles and matrix is clean and well bonded. Compared with the MgB2P/Cu composites fabricated by ex-situ powder metallurgy, the composites fabricated by reaction sintering technology exhibit higher density, hardness and lower electrical conductivity.