Surface treatment method of magnesium for the assembly of polymer and magnesium

A method to treat a magnesium surface with a bonded coupling of a mixture of a polymer and magnesium, comprising:

• (a) etching the magnesium surface with an acidic solution;
• (b) treating the magnesium surface in (a) with ultrasonic waves as a first surface treatment step;
• (c) treating the magnesium surface in (b) with an acidic solution as a second surface treatment step;
• (d) treating the magnesium surface in (c) with ultrasonic waves as a first silane coupling processing step;
• (e) treating the magnesium surface in (d) with acidic solution as a surface activation treatment step;
• (f) treating the magnesium surface in (e) with ultrasonic waves as a second silane coupling step;
• the step (a), is performed in an acidic solution mixing sulfuric acid, phosphoric acid and trace amounts of nitric acid, at 30˜60° C. for 10˜180 seconds;
• the step (b), proceeds with ultrasonic treatment with an alkali cleaning agent, at 30˜60° C. at 24˜100 kHz and 400 W for 10˜180 seconds;
• the step (c), proceeds a secondary etching with an acidic solution mixing sulfuric acid, phosphoric acid and trace amounts of nitric acid, at 30˜60° C. for 10˜180 seconds;
• the step (d), proceeds with a mixed solution of 0.1˜20 wt. % C2K2O4, 0.1˜10 wt. % Na2O3Si, 0.01˜1 wt. % C3H8O3 and 0.001˜0.01 wt. % C2OH24O10S2 adding 0.1˜1 wt. % Silane Coupling agent, at 30˜70° C., with 24˜100 kHz and 400 W for 10˜300 seconds;
• the step (e), proceeds with a mixed acidic solution of sulfuric acid and hydrochloric acid at a 30˜70° C. for 10˜300 seconds;
• and
• the step (f), proceeds with a mixed solution of 0.1˜20 wt. % C2K2O4, 0.1˜10 wt. % Na2O3Si, 0.01˜1 wt. % C3H8O3 and 0.001˜0.01 wt. % C2OH24O10S2 adding 0.1˜1 wt. % Silane Coupling agent, at 30˜70° C., with 24˜100 kHz and 400 W for 10˜300 seconds.