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