Effect of stacking fault energy on mechanical properties of ultrafine-grain Cu and Cu-Al alloy processed by cold-rolling

层错能对冷轧超细晶铜及铜铝合金力学性能的影响(英文)

Cu,Cu-2.2%Al and Cu-4.5%Al with stacking fault energies（SFE） of 78,35 and 7 mJ/m2 respectively were processed by cold-rolling（CR） at liquid nitrogen temperature（77 K） after hot-rolling.X-ray diffraction measurements indicate that a decrease in SFE leads to a decrease in crystallite size but increase in microstrain,dislocation and twin densities of the CR processed samples.Tensile tests at room temperature indicate that as the stacking fault energy decreases,the strength and ductility increase.The results indicate that decreasing stacking fault energy is an optimum method to improve the ductility without loss of strength.

在液氮温度下(77K)采用冷轧技术制备层错能分别为78、35和7mJ/m2的铜、Cu-2.2%Al和Cu-4.5%Al铜合金。X射线衍射分析表明,冷轧后样品的晶粒尺寸随着层错能的降低而降低,但微观应变、位错密度和孪晶密度则升高。室温拉伸实验表明,随着层错能的降低,铜合金的强度和塑性呈增加,说明降低层错能是一种能够同时提高冷轧铜合金强度和塑性的方法。