| Abstract:
In this study, morphology, mechanical and corrosion properties of Ni-P electroless coating was investigated using different pre-treatments on the Mg-Li (MA21) alloy. The results show that adding 125 g/l chromium trioxide and 110 ml/l nitric acid to the pickling solution can increase the uniformity of the intermediate layer and reduce the porosity of the Ni-P electroless coating. The MgF2 and LiF layer uniformity leads to the increase in the number of coating nucleation sites and a fine morphology. The corrosion rate of the MA21 sample, Ni-P electroless coating sample with 125 g/l CrO3 and 110 ml/l HNO3 was 63, 87 and 4 mpy, respectively. The test results of Ni-P electroless coating adhesion with pretreatment number 2 was double that of pretreatment number 1.
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