Surface modification of Mg73Zn26Y quasicrystal alloy using a high current pulsed electron beam treatment
Journal Title: Science Paper Online - Year 2012, Vol 7, Issue 2
Abstract
Mg73Zn26Y quasicrystal alloy was treated using the high current pulsed electron beam (HCPEB). Its surface microstructure features along with hardness and wear resistance were investigated by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and mechanical properties testing. The results show that the initial structure of the alloy includes black dendrite α-Mg, gray matrix Mg7Zn3 and petal-like quasicrystal Mg3Zn6Y. HCPEB treatment gives rise to a flat surface and the vanishing of coarse structures and phase boundaries due to the uniform distribution of alloying elements. Some fine precipitates are dispersedly distributed on the treated surface. Meanwhile, the surface hardness of the alloy is improved in different degrees after HCPEB treatment. The greatest improvement in surface hardness lies on the 2-pulse sample surface, and the value is about 2 362.8 MPa. Compared to the initial sample, the surface hardness of the 2-pulse sample is enhanced by 33.8%. Friction testing shows the friction coefficients of HCPEB-treated samples are significantly decreased. The friction coefficient of the 10-pulse sample is 0.16, whereas that of the initial sample is 0.26.
Authors and Affiliations
Bo Gao, Yi Hao, Fei Jiang, Wenfeng Zhang
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