The invention discloses a method for improving compactness of aluminum 
alloy micro-arc 
oxide coating, and belongs to the technical field of aluminum 
alloy surface modification. The method comprises the following steps of: 
grinding an aluminum 
alloy sample to be smooth, ultrasonically cleaning the aluminum alloy sample, putting the ultrasonically-cleaned aluminum alloy sample into 
electrolyte to perform micro-arc oxidization treatment, thereby preparing an aluminum-alloy micro-arc oxidation 
coating; and finally, performing 
laser scanning 
processing on the aluminum-alloy micro-arc oxidation 
coating by high-energy 
laser beams generated by 
laser unit equipment. The method disclosed by the invention can improve the structure of the aluminum-alloy micro-arc oxidation coating, so that a metastable phase in the coating is converted into a 
stable phase. The method effectively improves the problems that compaction of the coating is relatively poor as a result of porous characteristics, and the 
energy consumption for obtaining the micro-arc oxidation coating with good compactness is high, so that 
corrosion and 
wear resistance of the micro-arc oxidization coating is greatly improved; and moreover, the method is simple in process, is good in 
repeatability, and can be used for industrial large-area preparation.