The corrosion inhibition of AZ91 Dmagnesium alloy in 1g/L NaCl solution with sodium fluoride was detected by weightless

Tafel polarization curves

electrochemical impedance spectroscopy（E IS）and scanning electron microscopy（SEM）.With adding sodium fluoride into salt solution

protective coating MgF2 is formed on AZ91 Dsurface

which prevents Cl-adsorption on the interface between the sample and corrosive medium

therefore inhibiting the corrosion.With the concentration of sodium fluoride from 1g/L to 3g/L

the inhibition efficiency is increased

and the depth and quantity of pits become shallow and less with the corrosion potential moving positively and the capacitive loop of electrochemical impedance spectroscopy increases.Sodium fluoride is the corrosion inhibition of anode inhibited type.The inhibition efficiency is more than 50%and the highest value reaches 85%in 1g/L NaCl with NaF for 168 h.