Copper, as an excellent conductor material, is widely used in power, electronics, communication, and other fields. However, in actual applications, the strength, wear resistance, and corrosion resistance of pure copper often fail to meet the needs of complex working conditions. Therefore, people often improve the comprehensive performance of copper by alloying. However, adding alloy elements usually reduces the conductivity of copper. How to improve the strength of copper alloys while maintaining or improving their conductivity has become an important research topic in the field of materials science.



The conductivity of copper mainly depends on the migration ability of its free electrons. Pure copper has a high conductivity rate of about 58 MS/m (megasiemens per meter). However, when other elements are added to form alloys, the introduction of solute atoms will destroy the integrity of the copper lattice, causing electron scattering, and thus reducing the conductivity. Therefore, the key to improving the conductivity of copper alloys lies in optimizing alloy design and preparation technology.



Firstly, it is crucial to select appropriate alloy elements. Some elements such as silver (Ag), zirconium (Zr), magnesium (Mg), etc., have a relatively small impact on copper conductivity while significantly improving the strength and heat resistance of the material. For example, silver and copper almost do not form compounds in the solid solution state, so adding a small amount of silver (0.1%~0.2%) can increase the recrystallization temperature and high-temperature strength of copper without significantly sacrificing conductivity.



Secondly, the use of advanced preparation and processing technologies helps to improve the microstructure of copper alloys, thereby enhancing their conductivity and mechanical properties. For example, rapid solidification technology can refine grain size and reduce segregation, making the distribution of alloy elements more uniform; while large plastic deformation processes (such as equal channel angular pressing ECAP) can significantly refine the grain structure, enhance dislocation density, and thus achieve 'grain boundary strengthening' without significantly reducing conductivity.

　　Moreover, aging treatment is also an effective method. For copper alloys containing a small amount of precipitated strengthening phases (such as Cu-Ni-Si, Cu-Cr-Zr alloys), through reasonable solid solution and aging treatment, fine and uniform secondary phase particles can be precipitated in the matrix, which plays a reinforcing role while reducing interference to electron migration.



In recent years, the development of nanotechnology has provided new ideas for improving the conductivity of copper alloys. Studies have shown that the introduction of nanometric dispersed phases (such as Al₂O₃, ZrO₂, etc.) can significantly improve the strength and thermal stability of copper, and due to the low volume fraction of the dispersed phase, the impact on conductivity is relatively small.

　　In summary, although alloying often has a certain degree of negative impact on the conductivity of copper, it is possible to greatly improve the comprehensive performance of copper alloys while ensuring good conductivity by reasonably selecting alloy components, optimizing processing technology, and utilizing modern material preparation technology. This is of great significance for the research and development of high-performance conductive materials and also provides strong support for high-tech fields such as electronics, aerospace, and rail transportation.