Electrochemical corrosion behavior of Cu-40Ni-20Cr alloys with different grain sizes in solutions containing chloride ions
The electrochemical corrosion behavior of the two Cu-40Ni-20Cr alloys prepared by conventional casting(CA) and mechanical alloying(MA) with the different grain sizes was studied by using open-circuit potential(OCP),potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) methods in solutions containing chloride ions.The results show that the free corrosion potentials of the two alloys move towards negative values,corrosion currents increase and therefore corrosion rates become faster with the increase of chloride ion concentrations.EIS plots of CACu-40Ni-20Cr alloy are composed of single capacitive loop,while EIS plots of MACu-40Ni-20Cr alloy are composed of double capacitive loops in solution containing lower chloride ion concentrations.EIS plots of the two alloys have Warburg impedance with the increase of chloride ion concentrations.Corrosion rates of MACu-40Ni-20Cr alloy become faster than those of CACu-40Ni-20Cr alloy obviously in solutions containing the same chloride ion concentrations because MACu-40Ni-20Cr alloy is able to produce large concentrations of grain boundaries in the course of reduction in grain size by mechanical alloying.
Cu-Ni-Cr alloy grain size electrochemical corrosion microstructure
CAO Zhong-qiu BIAN Jing XUE Rong LIU Wei-hua
Department of Chemistry,Shenyang Normal University,Shenyang 110034,China
国际会议
2007年国际有色金属大会(International Conference of Nonfereous Materials 2007)(ICNFM)
长沙
英文
2007-11-28（万方平台首次上网日期，不代表论文的发表时间）