Compressive creep behavior of Mg-Sn-La alloys

The compressive creep behaviors of as-cast Mg-5Sn, Mg-5Sn-2La, Mg-6.5Sn-2La and Mg-8.5Sn-2La alloys are investigated in this paper. The compressive creep resistance of Mg-xSn-2La (x = 5 wt.%; 6.5 and 8.5 wt.%) alloy is much better than that of as-cast Mg-5Sn alloy at the applied stresses from 25 to 35 MPa and the temperature of 473 K, which is mainly due to the feather-shaped, rod-like and massive rare earth phases formed in Mg-Sn-La alloys. The calculated stress exponent n is 4.2, 5.6, 6.2, and 5.7, respectively for the as-cast Mg-5Sn, Mg-5Sn-2La, Mg-6.5Sn-2La and Mg-8.5Sn-2La alloys, which indicate that the dislocation creep is the rate controlling mechanism of these alloys.