等通道转角挤压Al-Li-Cu-Mg-Zr合金的循环形变行为

CYCLIC DEFORMATION BEHAVIOR OF ECAP Al-Li-Cu-Mg-Zr ALLOY

等通道转角挤压(ECAP)方法制备的Al-LI-Cu-Mg-Zr合金主要由晶粒小于1μm的等轴晶组成,循环形变时,ECAP Al-Li-Cu-Mg-Zr合金在应变幅较小时先出现短暂软化,然后持续硬化;在应变幅较大时持续软化直至断裂,ECAPAl-Li-Cu-Mg-Zr合金的Coffin-Manson曲线近似一条直线,这些特性均与文献报道的峰时效Al-Li-Cu-Mg-Zr合金有所不同。

Equal-channel angular pressed (ECAP) Al-Li-Cu--Mg-Zr alloy mainly consists of near equi-axial grains with size smaller than 1 mum. ECAP Al-Li-Cu-Mg-Zr alloy cyclically softens continuously to failure at higher strain amplitude of Deltaepsilon(p)/2 = 5.5 x 10(-3), but cyclically softens initially and then harden continuously to failure at lower strain amplitudes of Deltaepsilon(p)/2 = 5 x 10(-4) -2.6 x 10(-3). The Coffin-Manson curve of the ECAP Al-Li-Cu-Mg-Zr alloy shows an ideal straight line. All these properties are different from those reported previously for the conventional peak-aged Al-Li-Cu-Mg-Zr alloy.