Method for forming electrolytic copper plating film on surface of rare earth metal-based permanent magnet
AssigneeHitachi Metals, Ltd.
InventorsMasanao Kamachi, Koshi Yoshimura
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Abstract
An object of the present invention is to provide a novel method for forming an electrolytic copper plating film having excellent adhesion on the surface of a rare earth metal-based permanent magnet. The method of the present invention as a means for achieving the object is characterized in that after a magnet is immersed in a plating solution, a cathode current density of 0.05 A/dm2 to 4.0 A/dm2 for performing an electrolytic copper plating treatment is applied thereto over 10 seconds to 180 seconds to start the treatment.
Claims4
A method for forming an electrolytic copper plating film on the surface of a rare earth metal-based permanent magnet, comprising the steps of:
- immersing the rare earth metal-based permanent magnet in a plating solution containing Cu2+ ions,
- applying an increasing cathode current density in a range of 0.05 A/dm2 to 4.0 A/dm2 to the rare earth metal-based permanent magnet over 10 seconds to 180 seconds, wherein a cathode current density increase rate for applying the increasing cathode current density is 0.002 A/(dm2×sec) to 0.4 A/(dm2×sec), until a predetermined value of current density is reached, and then
- performing an electrolytic copper plating treatment at the predetermined value of current density.
A method for improving the adhesion of an electrolytic copper plating film formed on the surface of a rare earth metal-based permanent magnet, comprising the steps of:
- immersing the rare earth metal-based permanent magnet in a plating solution containing Cu2+ ions,
- applying an increasing cathode current density in a range of 0.05 A/dm2 to 4.0 A/dm2 to the rare earth metal-based permanent magnet over 10 seconds to 180 seconds, wherein a cathode current density increase rate for applying the increasing cathode current density is 0.002 A/(dm2×sec) to 0.4 A/(dm2×sec), until a predetermined value of current density is reached, and then
- performing an electrolytic copper plating treatment at the predetermined value of current density.
Dependencies are inferred from the claim text.