(1) All the elements without exception reduce the conductivity and thermal conductivity of the copper bar, where the elements are solidly dissolved in the copper bar, resulting in lattice distortion of the copper bar, so that the free electron directional flow of wave scattering, so that the resistivity increases, on the contrary, there is no solid solubility in the copper bar or few solid solution of the elements, brass strip has little effect on the conductivity and thermal conductivity of the copper bar, Special attention should be paid to the fact that the solid solubility of some elements in the copper bar decreases sharply with the decrease of temperature, and the precipitation of elemental and metallic compounds can not only strengthen the solid solution and dispersion of the copper bar alloy, but also reduce the conductivity. This is an important alloying principle for the study of high strength and high conductivity alloy, and it should be pointed out in particular that iron, silicon, wrong, The alloy composed of brass with chromium and copper rod is a very important alloy with high strength and high conductivity. Because the influence of alloying elements on the properties of copper bars is superimposed, CoCr-Zr alloy is the best alloy with high strength and high conductivity.

(2) The microstructure of copper base corrosion resistant alloy should be single-phase, so as to avoid electrochemical corrosion caused by the second phase in the alloy. For this reason, alloying elements added should have great solid solubility in copper rods, even infinite miscible elements. Single-phase brass rods, bronze rods and white copper rods used in engineering all have excellent corrosion resistance and are important heat exchange materials.