Method for forming holes, metal product, and metal composite

1. A method for forming holes to form holes in a surface of a metal part, comprising:

putting the metal part into a first solution as an anode;

applying a first voltage on the metal part to form the first holes in a surface of the metal part; and

cleaning and drying the metal part with the first holes;

wherein the first solution comprises a first organic solvent, chloride, and a phosphoric acid compound;

wherein before putting the metal part into the first solution, further comprising:

putting the metal part into a second solution as an anode; and

applying a second voltage on the metal part to form second holes in a surface of the metal part;

wherein the second solution comprises a second organic solvent and a substance capable of dissociating a compound including Cl − ;

wherein the second voltage is output by DC power supply, the second voltage is in a range of 60V to 100V, and

a current density is in a range of 1 A/dm 2 to 3 A/dm 2 ; in the step of applying the second voltage on the metal part, a temperature of the second solution is in a range of 50° C. to 70° C., and a time of applying the second voltage is in a range of 5 min to 20 min.

2. The method for forming holes of claim 1 , wherein the first organic solvent is selected from a group consisting of ethylene glycol, propylene glycol, diethylene glycol, glycerol, and any combination thereof.

3. The method for forming holes of claim 1 , wherein chloride is selected from a group consisting of sodium chloride, potassium chloride, copper chloride, ferric chloride, and any combination thereof.

4. The method for forming holes of claim 1 , wherein the phosphoric acid compound is selected from a group consisting of phosphoric acid, dihydrogen phosphate, monohydrogen phosphate, phosphate, metaphosphate, and any combination thereof.

5. The method for forming holes of claim 1 , wherein the first voltage is output by a gradual DC power supply, an increase rate of the first voltage is in a range of 1 V/s to 2 V/s, and a current density is in a range of 1 A/dm 2 to 10 A/dm 2 ; in the step of applying the first voltage on the metal part, a temperature of the first solution is in a range of 25° C. to 55° C., and a time of applying the first voltage is in a range of 10 min to 25 min.

6. The method for forming holes of claim 1 , wherein the substance capable of dissociating a compound including Cl − comprises a compound containing crystallization water.

7. The method for forming holes of claim 1 , wherein the substance capable of dissociating a compound including Cl − is selected from a group consisting of NaCl, KCl, FeCl 3 .6H 2 O, FeCl 3 , CuCl 2 .12H 2 O, CuCl 2 , and any combination thereof.

8. The method for forming holes of claim 1 , wherein the second solution further comprises a substance capable of dissociating a compound including at least one of Fe 3+ and Cu 2+ .

9. The method for forming holes of claim 8 , wherein the substance capable of dissociating a compound including Fe 3+ and Cu 2+ comprises a compound containing crystallization water.

10. The method for forming holes of claim 8 , wherein the substance capable of dissociating a compound including Fe 3+ is selected from a group consisting of FeCl 3 .6H 2 O, FeCl 3 , and any combination thereof, and the substance capable of dissociating Cu 2+ is selected from a group consisting of CuCl 2 .12H 2 O, CuCl 2 , and any combination thereof.

11. The method for forming holes of claim 1 , wherein after putting the metal part into the first solution, further comprising:

putting the metal part with the first holes into an electrolyte as an anode; and

applying a third voltage on the metal part to form third holes in the metal part;

wherein the metal part is made of a material selected from a group consisting of aluminum, aluminum alloy, a composite material of aluminum alloy and stainless steel, and any combination thereof, the third holes are located in a portion of the metal part containing aluminum or aluminum alloy.

12. The method for forming holes of claim 1 , wherein the metal part is made of a material selected from a group consisting of aluminum, aluminum alloy, stainless steel, and any combination thereof.