| W-Cu alloys have been broadly applied as contact materials in high voltage load switches. In this work, the tungsten (W) particulate reinforced Al2O3 dispersion strengthened copper base composites were successfully fabricated by using vacuum hot-press sintering furnace. The microstructures of the W/Cu-Al2O3 composite were analyzed with scanning electron microscope and transmission electron microscope respectively. The bending strength, electric conductivity and micro hardness of the composites were determined with universal material tester, vortex conductivity tester and digital micro hardness indenter respectively. The density of the composites was measured with the Archimedes method. The plastic deformation behavior of the composites at elevated temperature was investigated by using physical simulator of thermo-mechanical processes of the model 1500D Gleeble system. The results show that the microstructure of the W/Cu-Al2O3 composites is consisted of the matrix of the Al2O3 dispersion strengthened copper base and the reinforced phase of homogeneous distributed W particles. The composite has relative theoretical density of 99.8%. The bend fracture mechanism is brittle clevage and interface seperation. The true stress-strain curves of the W(50)/Cu-Al2O3 composite possess the steady rheological characteristic and dynamic recrystallization features. |
full paper (pdf, 864 Kb)