Metal magnet and motor using the same
View Patent ↗A metal magnet 10 including a magnet body 12 and a coating layer 14 over the magnet body 12 , in which the coating layer 14 has a Martens hardness of 2000 N/mm 2 or more and an elastic resilience of 25% or less, and a motor including the metal magnet 10.
1. A metal magnet comprising:
a magnet body; and
a coating layer over the magnet body, wherein the coating layer being a plated film has a Martens hardness of 2500-5000 N/mm 2 and an elastic resilience of 25% or less;
wherein the coating layer is a Ni-plated film, a Ni—B-plated film, a Ni—P-plated film, a Cu-plated film, a Zn-plated film, a Cr-plated film, a Sn-plated film, an Ag-plated film, an Au-plated film, an Al-plated film, or a metal-plated layer comprising an alloy of Ni, Cu, Zn, Cr, Sn, Ag, Au, or Al.
2. The metal magnet according to claim 1 , wherein the elastic resilience is 5% or more.
3. The metal magnet according to claim 2 , wherein the coating layer has a thickness from 1 to 50 μm.
4. A motor comprising the metal magnet according to claim 2 .
5. The metal magnet according to claim 1 , wherein the coating layer has a thickness from 1 to 50 μm.
6. A motor comprising the metal magnet according to claim 5 .
7. A motor comprising the metal magnet according to claim 1 .
8. The metal magnet according to claim 1 , comprising the coating layer as the outermost layer.
9. The metal magnet according to claim 1 , wherein the coating layer is the plated film produced using a plating bath comprising at least one selected from the group consisting of potassium chloride and sodium chloride.
10. The metal magnet according to claim 9 , wherein the total content of the potassium chloride and sodium chloride is 50 to 250 g/l.
11. The metal magnet according to claim 1 , wherein the plated film is a Ni-plated film.
12. A method of applying a metal magnet to a motor, the method comprising:
measuring a Martens hardness and an elastic resilience of the metal magnet comprising a magnet body and a coating layer being a plated film over the magnet body; and
selecting the metal magnet having a Martens hardness of 2500-5000 N/mm 2 and an elastic resilience of 25% or less,
wherein the coating layer is a Ni-plated film, a Ni—B-plated film, a Ni—P-plated film, a Cu-plated film, a Zn-plated film, a Cr-plated film, a Sn-plated film, an Ag-plated film, an Au-plated film, an Al-plated film, or a metal-plated layer comprising an alloy of Ni, Cu, Zn, Cr, Sn, Ag, Au, or Al.
13. The method of claim 12 , wherein the plated film is a Ni-plated film.