Effect Of Cold Deformation And Heat Treatment On Properties Of High-strength And High-conductivity Cu-Zn-Cr Alloy

In this paper, Effect of Cold Deformation and Heat Treatment on Properties of High-strength and High-conductivity Cu-17.0Zn-0.4Cr alloy was discussed. Cu-Zn-Cr alloy was prepared by Ingot Metallurgy. Using hardness measurement, tensile test at room, electrical resistance test, optical microscopy, XRD, SEM and TEM, the mechanical and electric properties and microstructure of Cu-Zn-Cr at different treatment were studied. Them were also analysed and explained in theory.We discovered, the strengthening mechanisms of Cu-Zn-Cr alloy include solution strengthening, strain-strengthening, and aging strengthening. Thermomechanical treatment can increase strength of Cu-Zn-Cr greatly. The alloy in aging after cold-drawing was influenced by interaction of precipitation and recrystallization. The precipitates not only can strengthen the matrix but also can restrain recrystallization.Electrical conductivity of alloy was influenced by reversion-recrystallization and precipitation of supersaturation solid solution. Reversion-recrystallization can increase electrical conductivity. Precipitation can also increase conductivity by reducing solid solubility in matrix.The optimal process of Cu-Zn-Cr alloy is extrusion, quench, cold-drawing, aging(450℃/1h), it's mechanical and electrical performance can reach :σ_b = 547.21Mpa,σ_r=55.1 %IACS.