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Pulsed magnetic field (PMF) has been imposed during solidification of Mg-Zn-Y alloy containing icosahedral quasicrystals phase (I-phase) in this work. The effects of vibration power on the solidification microstructure and mechanical properties of Mg93Zn6Y alloy were studied. The results show that the solidification microstructure of the Mg93Zn6Y alloy was further refined with increasing vibration power. The primary α-Mg in the alloy treated by PMF was changed from dendrites with the average grain size more than 1 mm untreated by PMF to rosette-like and polyhedral morphology with the average grain size of 122 μm. Moreover, the I-phase was changed from continuous thick skeletal to discontinuous fine reticular and particle-like morphology. The fraction of I-phase in the alloy treated by PMF was also reduced due to the increase of concentrations of Zn and Y elements inside grains. The mechanical properties of Mg93Zn6Y alloy treated by PMF were also improved significantly. The yield strength, ultimate tensile strength and elongation of the alloy treated by PMF at a vibration power of 350 W at room temperature were 162 MPa, 221 MPa and 1.99%, which were increased by 65%, 66% and 124% respectively, compared to those of the alloy untreated by PMF.

In situ 4.9wt.%TiB2/2024 composite has been successfully prepared by displacement reaction and spray deposition technique, and its microstructure and wear behavior were investigated. Experimental results have shown that in situ TiB2 particles uniformly distributed in the matrix, and the grain size of the composite was smaller than that of the alone 2024 alloy. Compared to the 2024 alloy, the composite showed accelerated aging process after solutionizing at 768K. The wear resistance of the composite improved considerably and a maximum wear resistance were obtained after over aging.