含稀土元素的Mg-Al合金在NaCl溶液中腐蚀产物膜的研究

STUDY ON CORROSION PRODUCT FILM OF MAGNESIUM-ALUMINUM ALLOYS CONTAINING RARE-EARTH ELEMENT IN NaCl SOLUTION

利用多种表面分析手段比较研究了纯Mg和Mg - 8Al、Mg - 8Al-RE等镁铝合金在Mg(OH) 2 饱和的 3 5 %NaCl溶液中的腐蚀产物膜的形貌及结构 .发现Al元素的加入使镁合金表面形成含Mg、Al的复杂氧化物 ,有利于提高镁合金耐腐蚀性 .稀土元素RE的加入有利于提高Al元素在氧化膜中的含量 ,形成具有三层结构的产物膜 ,进一步提高了Mg

The corrosion resistance of magnesium-aluminum alloys is closely related to the corrosion product film formed on the alloy's surface.The morphology and structure of the corrosion product film on pure Mg, Mg-Al and Mg-Al-RE alloys in the solution containing Cl\+- were examined by the various surface analysis techniques including EMPA,EDS,SEM,TEM,XRD,AES etc.The results indicated that the elemental aluminum is conducive to the corrosion resistance of alloys,but its beneficial effect is limited and unstable.The RE addition can obviously increase the Al concentration in corrosion product film.Also,the distribution of Al in corrosion product film of Mg-Al-RE alloys was broadened due to the addition of RE.It indicated that the RE element promoted the formation of protective film containing elemental Al.