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Copper tungsten composite material having a high density, high strength, high hardness and good ductility, good conductivity, thermal conductivity and thermal expansion coefficient and other unique properties of the electrodes so that it is widely used as an electrical contact, electrical processing, electronic packaging materials, etc. the function and structure of the device. Tungsten-copper composite material because of its good performance, low cost, that is a great potential for development and application prospects of new functional materials. Tungsten copper composites are mainly concentrated in the density, the preparation process, the hot deformation behavior of tungsten-copper composite, both at home and abroad also rarely reported. This paper, vacuum hot pressing sintering high-performance composite fine grain tungsten copper, the copper content of its performance and organizational and study its thermal deformation behavior, to establish the constitutive equation of tungsten-copper composite, using dynamic material model tungsten copper composites processing maps provide a theoretical basis for the actual production of tungsten-copper composite. This article in the sintering temperature of 950 ° C, pressure 30MPa, the degree of vacuum of 5 × 10-3Pa, vacuum hot pressing sintering under the 2h the conditions of the sintering time on different copper content of copper tungsten powder to prepare a near full densification of the copper and W -Cu50%, W-Cu75% composites. Three material composition, microstructure, density, hardness and conductivity testing and observation, the copper content of the organizational structure and properties of tungsten-copper composite and sintering densification mechanism. The results show that: the W-Cu composite materials, vacuum hot pressing sintering the densification mechanism to the rearrangement of the particles, the plastic deformation and the relative sliding, the copper content of the powder will increase the overall fluidity and plastic deformation, thereby increasing the density and conductivity; tungsten hinder the copper grain growth, with the increase in the tungsten, the finer grains, the higher the hardness. W-Cu50% W-Cu75% composites and copper density, micro-hardness, conductivity were 99.12%, 99.63%, 99.81%, 133HV, 110 HV, 80HV, 68.90% IACS, 86.10% IACS, 92.80 % IACS. A one-way compression test, hot deformation behavior of the three materials prepared by vacuum hot pressing. W-Cu50% W-Cu75% composite flow stress - true strain curve under the test conditions for dynamic recrystallization; pure copper flow stress - true strain curves at 650 ° C, the strain rate of 5s-1 and 1s-1, belongs to the dynamic recovery type, compared with the dynamic recrystallization type under other conditions. Lower strain rate and deformation temperature are conducive to dynamic recrystallization occurs: the greater the strain rate, the higher the flow stress, the finer grain; higher deformation temperature, the flow stress is lower, grain Vietnam thick. Tungsten to dynamic recrystallization to provide a non-homogeneous nucleation core, reducing the copper dynamic recrystallization temperature. The hyperbolic sine relationship can be described in three kinds of materials under different stress flow stress, deformation temperature and strain rate relationship obtained W-Cu50% W-Cu75% composites and pure copper heat deformation activation energy, and the establishment of a constitutive equation. Constructing the hot workability view of the three materials, dynamic material model to study the variation of the thermal processing, and combining microstructure analyzed. The results show that: the tungsten-copper composite instability mechanism for the separation of tungsten copper interface due to the high strain rate micro-cracks in the heat distortion; the pure copper instability mechanism for local rheological instability; combined with thermal processing Figure and organization, the the material best hot deformation process.
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