Microstructure and properties of single crystal copper prepared by hot type horizontal continuous casting process

Abstract

Single crystal copper exhibits superior conductivity compared to polycrystalline copper due to its lack of internal grain boundaries, finding extensive application in the field of electronic information transmission. The hot horizontal continuous casting method, employed for the fabrication of single crystal copper rods, directly influences their production and quality. This study simulated the effects of process parameters on the temperature and solidification fields during hot horizontal continuous casting, utilizing the directional solidification method. Comparative analyses of microstructural and mechanical properties between fabricated single and polycrystalline copper rods were conducted to provide a scientific basis and technical support for the optimization and application of copper rod materials in specific fields. Findings indicate that the melt temperature minimally affects the position of the solid-liquid interface in hot continuous casting. An increase in mold temperature causes a slight outward shift in this interface, while an increase in casting speed significantly displaces it outward, raising the risks of breakage and leakage. The interior of single crystal copper rods primarily contains a sparse distribution of discrete dislocations, forming a preferred orientation pattern dominated by < 100> texture, with a fracture mode of microporous growth. In contrast, polycrystalline copper rods contain numerous dislocation cells, forming <111>+<110> discrete textures, which are more varied than those in single crystal rods, leading to a ductile dimple-microporous aggregation fracture mode. The conductivity and elongation of single crystal copper rods are markedly higher than those of polycrystalline rods, thus affirming their exceptional electrical conductivity and plastic processing capabilities.