双级时效对含Sc的Al-Cu-Li-Zr合金组织与性能的影响

Effect of double-stage aging treatment on microstructure and mechanical properties of Al-Cu-Li-Zr alloy containing Sc

通过合金室温力学性能测试及时效组织的透射电镜分析,研究双级时效对含Sc的Al-Cu-Li-Zr合金的组织与性能的影响。研究结果表明:较适宜的双级时效工艺为120℃/2 h+160℃/24 h,在此工艺条件下,合金既具有较高的强度,又具有较好的塑性;双级时效能促进T1相弥散、细小析出;与T8峰时效态相比,采用先低温后高温的双级时效工艺可使合金在不降低强度的情况下提高合金的伸长率。

The effect of double-stage aging treatments on the microstructure and mechanical properties of Al-Cu-Li-Zr alloy containing Sc were investigated by using TEM and tensile test at room temperature.The results show that the proper double-stage aging treatment of the alloy is 120 ℃/2 h＋160 ℃/24 h,and under this condition,the alloy reaches an optimal combination of the strength-ductility.Double-stage aging makes phase T1 precipitation distribute more dispersively and uniformly in the alloy.Compared with phase T8 peak-aged state,double-stage aging treatment can increase the elongation and remain high level of strength.