Mechanical properties of the hot-rolled Mg-12Gd-3Y magnesium alloy

摘要

Tensile and high cycle fatigue (HCF) properties of the hot-rolled Mg-12Gd-3Y (wt.%) magnesium alloy have been investigated. The magnesium alloy exhibits a fatigue strength of about 150 MPa, which is much higher than that of the commercial Mg-8Al-Zn alloy AZ80. Aging heat-treatment (T5) improved the fatigue life of the Mg-12Gd-3Y alloy. Fatigue cracks nucleated at the intense slip bands in the as-rolled alloy. After T5 treatment, however, the fatigue crack nucleation site shifted to the phase boundaries between MgGdY particles and Mg matrix. T5 heat-treatment retarded the crack initiation and thus improved the fatigue life of the Mg-12Gd-3Y alloy.