Abstract: In this article,the microstructure and mechnical properties of composites produced by the reaction between MoSi₂ and B₄C during the hot pressing process were studied.The results indicated that the composites are mainly consisted of MoSi₂,Mo₂B₅ and small amount of SiC and Si.The mechnical proper ties of composites which compared with monolith Mo Si₂ material were greatly improved.Bending strength and fracture toughness reached the highest value of 380MPa and 3.9MPa· m^1/2,respectively,at ambient temperature when B₄C addition is of 10%.On the other hand,hardness of the composites increased with the increasement of B₄C addition.

Key words: molybdenum disilicide, boron carbide, microsctructure, mechnical properties