| The 1990s, the magnesium alloy development application upsurge has been raised in the global scope. Due to the unique, magnesium is becoming the third-largest metal engineering materials after the steel and aluminum, known as the "21st Century Green Engineering." However, poor corrosion resistance has become to play a major factor by constraining its performance advantage. Therefore, the appropriate surface treatment can enhance the corrosion resistance of the existing magnesium alloy which has important practical significance. Chemical conversion treatment because of its simple, low cost, is the effective method of magnesium alloy corrosion. This reaction is carried on in the acidity or neutral solution including in six price chromium, but the chromium is extremely harmful to the human body health. At present, rare earth transformation processing is widely paid attention to in magnesium alloy non-chromium transformation processing. By rare earth primarily salt solution production transformed membrane non-toxic, is small to the environment and human body's harm, can obviously improve the corrosion resistance of magnesium alloys.In this paper, two kinds of magnesium alloy rare earth chemical conversion treatment liquid formula and related processes has been developed. the orthogonal experiment to determine initially influencing factor's primary and secondary order has been used, and various factors to transform the membrane growth process and the performance influence have been analyzed. Based on this, the technological parameter to become film thickness, the superficial appearance to the rare earth transformation membrane, the corrosion resistance influence has been analyzed.Next, In this paper, the hydrogen corrosion experiment and others different testing method to study the magnesium alloy two kind of transformation membrane film anti-corrosive performance by through the intravenous drip experiment has been analyzed, the immersion corrosion experiment, and the best technological parameter next two kind of transformation membrane appearance, binding force, ingredient and others basic information has been researched. By through metallography microscope, SEM, XRD and so on. The result indicate that two kind of rare earth transformation membrane craft could enable the magnesium alloy the anti-corrosive performance to have the very big improvement; Two kind of transformed membranes are even, are compact, the complete cover substrate surface. Contrasts two kinds of rare earth transformation membrane, the cerium transformation membrane slightly surpasses the misch metal transformation membrane in the appearance structure, the anticorrosion performance aspect, but may provide the temporary surface corrosion protection for the magnesium alloy; but all of them can provide the temporary surface corrosion protection for the magnesium alloy; Moreover the misch metal compares the cerium to be cheap in the price, The misch metal preparation transformation membrane has been used may save the cost, therefore two kind of membranes both have the good promoted application prospect.Finally, In this paper, the scanning electronic microscope further analyzed differently separately two kind of magnesium alloy rare earth transformation membrane surface appearance has been used which the membrane time formed, and has proposed the magnesium alloy rare earth chemical conversion membrane's formation principle, and formed the mechanism to two chemical conversion membrane's structure to carry on the preliminary discussion, then the fact show that some tests have been given a reasonable explanation. The investigation will broaden RE surface treatment in the practical application of magnesium alloys.
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