Compressive strength and yield asymmetry in extruded Mg–Zn–Ho alloys containing quasicrystal phase

Two alloys, Mg96.9Zn2.7Ho0.4 and Mg93Zn6Ho, containing a quasicrystal phase were extruded at various temperatures to produce different grain sizes and tested at room temperature in tension and compression. For larger grains the strength of the Mg93Zn6Ho alloy was almost twice that of the Mg96.9Zn2.7Ho0.4 alloy. Yield stresses approached 300 MPa as the grain sizes decreased to 1 μm. In the case of the Mg93Zn6Ho alloy, at grain sizes less than about 2 μm, yield stresses in compression become higher than in tension.