铝合金在氯化铵溶液中的缓蚀研究

A STUDY OF CORROSION INHIBITION FOR ALUMINIUM AND ITS ALLOY IN NH C1 SOLUTIONS

借助于电化学方法和SEM技术研究了铝合金在氯化铵溶液中的阳极行为.所研制的铝合金较之纯铝具有明显的耐腐蚀效果,在加有少量(NH_4)_2CrO_4(C_2H_5)_4NBr或明胶作为缓蚀剂的NH_4Cl体系中,它们的耐蚀能力更强,阳极极化下的自放电速度很低,当电流密度为i_a=15～50mA/cm^2时,电极效率(η)可达99%;同时电极表面的孔蚀现象受到一定的抑制,腐蚀变得更均匀.

Pure aluminium and five alloy as negative electrode material have been studied by electrochemical technique and SEM observation. The results showed that the inhibition effects of these alloys in NH_4Cl solutions were much better than pure Al. Al alloy electrode had a lower self-discharge rate under anodic polarization conditions and a longer wetting storage life than pure Al electrode. Its electrode efficiency was high to 99% over a range of current density from 15 to 50 mA/cm^2 in 1 mol/L NH_4Cl-0.001 mol/L (NH_4)_2CrO_4-0.001 mol/L (C_2H_5)_4NBr or 1 mol/L NH_4Cl-0.2ppm gelatine solutions. The pitting corrosion of the electrode was inhibited by these inhibitors above