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Indexed by:会议论文

Date of Publication:2015-01-01

Included Journals:CPCI-S

Page Number:465-469

Key Words:Magnesium alloy; surface treatment; corrosion resistance; high current pulsed electron beam; nanostructure

Abstract:Surface microstructure and corrosion resistance of AZ91 magnesium alloy was studied after high current pulsed electron beam (HCPEB) treatment with parameters of accelerating voltage 27 kV, energy density 3 J/cm(2) and 1 similar to 30 pulses. With the increasing HCPEB pulses, the eutectic and beta-Mg17Al12 phases were dissolved gradually into alpha-Mg matrix and the element distribution became homogenous. The modified surface layer showed a fluctuant aspect at the beginning and turned to be flat eventually with a depth of similar to 10 mu m. The nanostructure composed of Mg3.1Al0.9 grains and Mg17Al12 network was formed in the modified surface layer and led to a significant improvement in corrosion resistance. The cathodic current density in 3.5 wt. % NaCl solution decreased nearly two orders of magnitude as compared with the initial sample.