Of Cu-cr-zr And Cu-zn-cr-zr Alloy Aging Characteristics Of Study

Cu-Zn-Cr-Zr conducting bar alloy and Cu-Cr-Zr end ring alloys used for superpower asynchronous traction motor rotor were prepared by Ingot Metallurgy. Using hardness measurement, tensile test at room and higher temperature, electrical resistance test at room and higher temperature, optical microscopy, XRD, SEM, and TEM, the mechanical and electric properties and the microstructure of above alloys at different treatment were studied. Them were also analysed and explained in theory. The results show that:The first, Cu-Zn-Cr-Zr alloy is a typical aging strengthing alloy; the optimal process of bar alloy is extrusion-quench-cold-drawing-aging(450PC/4h), it's mechanical and electrical performance can reach o b=467MPa, o 0.2=390MPa, 8 5=20.8%, a r=64.6%IACS; the optimal process of end ring alloy is hot-forging-solution-aging(450癈/4h), it's mechanical and electrical performance can reach o b=342MPa, o 0a=216MPa. 6 5=27.8%, o r=74.3%IACSoThe second, above alloys not only have good strength and conductibility at room temperature but also have good strength at high temperature. Bar alloy can hold o b=274MPa and o o2=250MPa at 350癈 while end ring alloy can hold o b=200MPa and o 02=l65MPa at350癈.The third, the strengthening mechanisms of above alloys mainly include solution strengthening, strain-strengthening and aging strengthening. Thermomechanical treatment(solution-cold-drawing-aging) can increase alloys' strength greatly. The alloy in aging after cold-drawing was influenced by the interaction of precipitation and recrystaUization. The precipitates not anly can strengthen the matrix but also can restrain recrystaUization.The fourth, electrical conductivity of alloys was influenced by reversion-recrystaUization and precipitation of supersaturation solid solution. Reversion-recrystaUization can increase electrical conductivity. Precipitation can also increase conductivity by reducing solid solubility in matrix.FinaUy, high-conductivity of aUoys come from disperse and duplex phase structure. It's conducting mechanism can be explained by cubic conducting unit model.