The effects of Ca on the microstructure and mechanical properties of Mg

93

Zn

6

Y

1

alloy containing icosahedral quasicrystals phase（I-phase） were investigated. The results show that the microstructures of alloys are refined by Ca addition. The grain size of primary α-Mg phase is further decreased with increasing in Ca contents.Moreover

the morphology of second phase is changed from thick skeletal to discontinuous reticular

and the volume fraction of the second phase is further reduced.The mechanical properties of the alloys are further enhanced with the increase of Ca contents. With 0.4%Ca addition

the tensile strength and elongation of the alloy reach 221 MPa and 4.2%

respectively

which are increased by 66.2% and 90.9% compared with those of the Mg

93

Zn

6

Y

1

alloy.