| Copper and copper alloy is the traditional high electrical and thermal conductivity materials,which is widely used in electronics & electronics appliance industrial sector, but the application of copper and copper alloy is restricted for lake of strength and heat resistance. How to overcome the shortcoming that the conductivity and strength can not be best of both worlds is an important issue in the copper composites material research. The Particle-reinforced copper matrix composites, in particular the ceramic particle-reinforced copper matrix shows a good prospects to resolve this issue. TiB2 is a good reinforcement for composites material because of having a lot of excellent characteristics such as high hardness, high strength, and good resistance to abrasion, low coefficient of thermal expansion, good electrical conductivity, and good heat conductivity. Mechanical alloying (MA) is a solid-state powder processing technique involving repeated cold welding, fracturing, and rewelding of powder particles in a high-energy ball mill.In this paper, by using the mechanical alloying method, produces Cu-TiB2 composite powder, and then using the pressing and sintering to prepare Cu-TiB2 composites. The impacts of ball mill technology, pressing technology and sintering technology to the effect of Cu-TiB2 composites were discussed. The result show:1) The particle size of mixed powder decreased and the XRD peaks are weakened with the extension of milling time. In the initial stage of ball milling, the particle size of powder decreased quickly, but it tends to a stable number.2) The Cu-TiB2 Composites prepared by Mechanical Alloying has high hardness, high strength and low resistivity.The hardness and strength of the composites increased, the resistivity decrease when the TiB2 content increased.3) The most reasonable preparation technology involves: milling time 60h,pressing stress 400MPa, sintering temperature 900℃,holding time 2.5h.
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