关键词: Cu-0.2, Al₂O₃弥散强化铜合金, 冷拉拔变形, 微观组织, 织构, 力学性能, 韧性断裂

Abstract:

The annealed Cu-0.2%Al₂O₃ dispersion strengthened copper alloy was cold-drawn with the maximum deformation amount of 99%. The effect of cold drawing deformation on the microstructure, texture, electrical conductivity and mechanical properties of the alloy was studied by means of optical microscope, scanning electron microscopy, X-ray diffraction and mechanics tester. The results show that with the increase of cold drawing deformation amount the microstructure of the alloy changes from coarser elongated structure to fibrous one. When the deformation amount is 0%, the textures of Cu-0.2%Al₂O₃ alloy are composed by brass {011}<211> and cube {001}<100> textures. After 60% cold deformation amount some cube and brass textures are gradually transformed into goss {011}<100> and copper {112}<111> texture. And the cold drawing deformation amount has almost no effect on the conductivity. The microhardness of the alloy increases from 141 HV0.3 to 161 HV0.3. While the tensile strength increases from 492 MPa to 637 MPa, yield strength increases from 452 MPa to 605 MPa, and the elongation decreases from 14.0% to 1.0%, respectively. It is found that the tensile fracture of the alloy is ductile. Therefore, it can be concluded that the Cu-0.2%Al₂O₃ dispersion strengthened copper alloy has excellent plastic workability.

Key words: Cu-0.2%Al₂O₃ dispersion strengthened copper alloy, cold drawing deformation, microstructure, texture, mechanical properties, ductile fracture