铸造-冷挤压成形铜包铝线工艺及微观组织

采用铸造-冷挤压工艺制备铜包铝复合线材。通过对制品的微观组织进行分析表明,在锥形变形区,界面处铝晶粒均开始得到细化,而中心晶粒直径较大,基本保持原态,组织极不均匀,区域分界非常明显;铜铝边界上铜的晶粒也明显得到细化,铜的中心晶粒直径较大,但两区域形态均为等轴形晶粒,变形体外表面铜的微观组织最为细小,但晶粒形状不很规则。制品全挤出后,铜铝晶粒基本得到完全细化,而且非常细小均匀,铝芯平均直径小于5μm,铜皮平均晶粒直径在10μm左右。界面相晶粒尺寸非常细小均匀,与铜铝两相结合良好。

Fabrication technology and microstructure of aluminum/copper clad composites formed by casting-cold extrusion

Aluminum/copper clad composite was fabricated by casting-cold extrusion forming technology and microstructure of products was observed and analyzed.The results show that aluminum grains at the interface are refined in cone-shaped deformation zone,but the grains in the center maintain the original state and grain size is non-uniform.A clear boundary is presented between the refined area and center area.In contrast,copper grains in the radial profiles has been significantly refined.In the center area of the copper,the grains size is bigger than that at boundary.On the surface of the deformable body the grain size is the smallest,but with irregular grain morphology.After the product is entirely extruded,all the copper and aluminum grains are refined with small and uniform morphology.In the center area,the average diameter of aluminum grains is less than 5μm,and the copper grain on the surface is about 10μm.At the interface the grain size is very small,with a good combination of copper and aluminum.