Both the Al-5wt%Mg powder mixture and Al-5wt%Mg/SiCp composite mixture were separately ball-milled for 50h, followed by compaction under a pressure of 350MPa. To obtain the bi-materials, the compacted Al-5wt%Mg and Al-5wt%Mg/SiCp composites were bonded by sintering at 873K-1173K for 1-3h. At a relatively low temperature, 873K, the sound bi-materials could not be obtained. However, the bi-materials with the macroscopically bonded interface between Al-Mg and its composite were obtained at temperatures higher than 873K. The length of a well-bonded interface became longer with increasing temperature and time, indicating the improved contact in the bonded interface. The relative density in the bi-materials increased as the sintering temperature and time increased, and the bi-materials sintered at 1173K for 5h showed the highest density.