Method of making Nd—Fe—B magnetic materials with reduced heavy rare earth metals
AssigneeGM Global Technology Operations LLC
InventorYucong Wang
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Abstract
A method of making a magnetic material includes a step of providing a first material in the form of a core powder containing Nd, Fe and B. The first material is combined with the second material to form a powder combination. The second material includes a component selected from the group consisting of Dy, Tb, and combinations thereof. The powder combination is encapsulated to form an encapsulated powder combination. A magnetic field is applied to the powder combination during encapsulation and thereafter to align the magnetic dipoles therein. The encapsulated powder combination is isostatically pressed with heat to form the magnetic material.
Claims21
A method of making a magnetic material, the method comprising:
- a) providing a first material including a core powder containing Nd, Fe and B;
- b) combining the first material with a second material to form a powder combination, the second material comprising a component selected from the group consisting of Dy, Tb, and combinations thereof;
- c) encapsulating the powder combination to form an encapsulated powder combination by selectively laser sintering the powder combination to form a solid skin defining a predetermined pattern;
- d) applying a magnetic field during encapsulating and thereafter to the powder combination to impart magnetization thereto;
- and
- e) isostatically pressing the encapsulated powder combination while heating such that the temperature of the powder combination increases from a first temperature to a second temperature to form a pressed composition.
A method of making a magnetic material, the method comprising:
- a) providing a core powder containing Nd, Fe and B;
- b) combining the core powder with a rare earth metal-containing powder to form a powder combination;
- c) encapsulating the powder combination to form an encapsulated powder combination by selective laser sintering the powder combination to form a solid skin defining a predetermined pattern;
- d) applying a magnetic field to the powder combination to impart magnetization thereto;
- e) isostatically pressing the encapsulated powder combination with an inert gas at pressures from 50 MPa to 350 MPa, the encapsulated powder combination being heated such that the temperature of the powder combination increases from a first temperature of about 5° C. to 35° C. to a second temperature of about 500° C. to 1000° C. to form a pressed composition;
- and
- f) heating and sintering the pressed composition at a temperature from about 500 to 1000° C.
Dependencies are inferred from the claim text.