Microstructure and properties of copper alloy based nano composite for spot welding electrode

Copper alloy-based composites were successfully prepared using PM method with mechanically alloyed powders for spot welding electrode(CuCrZr/AlN).Microstructure and properties were characterized using transmission electron microscope, scanning electron microscope etc.Their electrical conductivity, thermal conductivity and softening temperature were measured.Results show that with the increasing of the contents of AlN, the electrical and thermal conductivity both decrease while the softening temperature increases. When the content of AlN is 0.4wt%, its softening temperature reaches 900℃, while its electrical conductivity is about 45%IACS (international annealling copper standard) and its thermal conductivity is about 197 W/m·K.When the content of AlN is 0.2wt%, the composite has good comprehensive properties and is suitable for spot welding electrode.