| Cu-17Zn-0.4Cr (wt %) alloys which were prepared by half continuous cast way. Through hardness measurement, tensile test at room temperature, electrical resistance test at room temperature, microstructure analysis, XRD analysis, SEM and TEM analysis methods, the mechanical and electric properties and the microstructure of above alloys at different work and heat treatment technologies were studied .Some of them were also analyzed and explained in theory. The results show that:The first, Cu-Zn-Cr alloy is a typical aging strengthening alloy;under this experiment condition, the better technology is that the alloys are rapid hot rolling and quenching (the starting rolling temperature is 930℃) ,then precipitated at 450℃ for 1 hour.The second, rapid hot rolling and quenching can hold the effects of working hardening.The third, the strengthening mechanisms of above alloys mainly include solution strengthening, work strengthening and aging strengthening. Thermo-mechanical treatment (rapid hot rolling and quenching and aging) can increase alloys' last strength greatly, and influence the conductivity of the alloy little. The alloy in aging after rapid hot rolling and quenching was influenced by the interaction of precipitation and recrystallization. The precipitates not only can strengthen the matrix but also can restrain recrystallization.The fourth, electrical conductivity of alloys was influenced by reversion recrystallization and precipitation of supersaturating solid solution. Reversion recrystallization can increase electrical conductivity. Precipitation can also increase conductivity by reducing solid solubility in matrix.Finally, high-conductivity of alloys come from disperse and duplex phase structure. It's conducting mechanism can be explained by cubic conducting unit model.
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