Ordering and disordering of in situ grown MgAl-layered double hydroxide and its effect on the structural and corrosion resistance properties

作     者：Muhammad Ahsan Iqbal Michele Fedel 

作者机构：Department of Industrial Engineering University of Trento 

出 版 物：《International Journal of Minerals,Metallurgy and Materials》 (矿物冶金与材料学报（英文版）)

年 卷 期：2019年第26卷第12期

页      面：1570-1577页

核心收录：

学科分类：08[工学] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 

基　　金：Università degli Studi di Trento  UNITN 

主　　题：layered double hydroxide calcination in situ growth thin films corrosion protection 

摘      要：A MgAl-layered double hydroxide(MgAl-LDH)protective film was developed on AA6082 substrates via the in situ hydrothermal growth method to obtain a distinct cauliflower-like LDH structure,and coated substrates were further heat-treated in air at temperatures from 100 to 250℃ to further improve the corrosion resistance of MgAl-LDH by taking advantage of the LDH memory effect;also,the effect of calcination on MgAl-LDH structural stability and the corresponding corrosion resistance properties were *** structural characterization of uncalcined and calcined LDH films were examined using scanning electron microscopy,energy-dispersive spectroscopy,X-ray diffraction,thermogravimetric analysis,differential scanning calorimetry,and Fourier transform infrared *** corresponding corrosion protection efficiency of the developed coating was studied through potentiodynamic polarization experiments and by electrochemical impedance *** with uncalcined MgAl-LDH,the calcined film showed a relatively lower corrosion current density and a higher impedance value,especially after heat treatment at 250℃.The findings demonstrate that calcination strongly affects the oriented growth of the LDH and causes an increase in the surface area and contraction of the basal spacing,which in turn caused a compact structure that substantially influenced the LDH corrosion resistance properties.