Magnetic compound and method of producing the same

Patent metadata

Field	Value
Publication number	US-10351935-B2
Application number	US-201514844478-A
Country	US
Kind code	B2
Filing date	Sep 3, 2015
Priority date	Sep 9, 2014
Publication date	Jul 16, 2019
Grant date	Jul 16, 2019

Abstract

Provided is a magnetic compound represented by the formula (R(1-x)Zrx)a(Fe(1-y)Coy)bTcMdAe (wherein R represents one or more rare earth elements, T represents one or more elements selected from the group consisting of Ti, V, Mo, and W, M represents one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag, and Au, A represents one or more elements selected from the group consisting of N, C, H, and P, 0≤x≤0.5, 0≤y≤0.6, 4≤a≤20, b=100−a−c−d, 0<c<7, 0≤d≤1, and 1≤e≤18), in which a main phase of the magnetic compound includes a ThMn12 type crystal structure, and a volume percentage of an α-(Fe,Co) phase is 20% or lower.

First claim

What is claimed is:

1. A magnetic compound represented by (R (1-x) Zr x ) a (Fe (1-y) Co y ) b T c M d A e , the magnetic compound comprising
a ThMn 12 type crystal structure, wherein
a volume percentage of an α-(Fe,Co) phase is 20% or lower,
R represents one or more rare earth elements,
T represents one or more elements selected from the group consisting of Ti, V, Mo, and W,
M represents one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag, and Au,
A represents one or more elements selected from the group consisting of N, C, H, and P,
0x≤0.5,
0≤y≤0.6,
4≤a≤20,
b=100−a−c−d,
0<c<7,
0≤d≤1, and
1≤e≤18.

2. The magnetic compound according to claim 1 , wherein
0≤x≤0.3, and
7≤e≤14.

3. The magnetic compound according to claim 1 , wherein
a region surrounded by 0<c<7, x≥0, c>−38x+3.8 and c>6.3x+0.65 is satisfied.

4. A method of producing the magnetic compound according to claim 1 , the method comprising:
a step of preparing molten alloy having a composition represented by (R (1-x) Zr x ) a (Fe (1-y) Co y ) b T c M d ;
a step of quenching the molten alloy at a rate of 1×10 2 K/sec to 1×10 7 K/sec; and
a step of crushing solidified alloy, which is obtained by the quenching, and then causing A to penetrate into the crushed alloy, wherein
R represents one or more rare earth elements,
T represents one or more elements selected from the group consisting of Ti, V, Mo, and W,
M represents one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag, and Au,
0≤x≤0.5,
0≤y≤0.6,
4≤a≤20,
b=100−a−c−d,
0<c<7,
0≤d≤1, and
A represents one or more elements selected from the group consisting of N, C, H, and P.

5. The method according to claim 4 , further comprising:
a step of performing a heat treatment at 800° C. to 1300° C. for 2 hours to 120 hours after the quenching step.

6. A rare earth element-containing magnetic compound comprising
a ThMn 12 type crystal structure, wherein
a lattice constant a of the crystal structure is within a range of 0.850 nm to 0.875 nm,
a lattice constant c of the crystal structure is within a range of 0.480 nm to 0.505 nm,
a lattice volume of the crystal structure is within a range of 0.351 nm 3 to 0.387 nm 3 ,
a hexagon A is defined as a six-membered ring centering on a rare earth atom, which is formed of Fe (8i) and Fe(8j) sites,
a hexagon B is defined as a six-membered ring which includes Fe (8i) and Fe(8j) sites in which Fe (8i)-Fe (8i) dumbbells form two sides facing each other,
a hexagon C is defined as a six-membered ring which is formed of Fe (8j) and Fe(8f) sites and whose center is positioned on a straight line connecting Fe (8i) and the rare earth atom to each other,
a length of the hexagon A in a direction of axis a is shorter than 0.611 nm,
an average distance between Fe (8i) and Fe (8i) in the hexagon A is 0.254 nm to 0.288 nm,
an average distance between Fe (8j) and Fe (8j) in the hexagon B is 0.242 nm to 0.276 nm, and
an average distance between Fe (8f) and Fe (8f) facing each other with the center of the hexagon C interposed therebetween in the hexagon C is 0.234 nm to 0.268 nm.

7. A magnetic powder which is made of a compound represented by (R (1-x) Zr x ) a (Fe (1-y) Co y ) b T c M d A e , the magnetic powder comprising
a ThMn 12 type crystal structure, wherein
a volume percentage of an α-(Fe,Co) phase is 20% or lower,
R represents one or more rare earth elements,
T represents one or more elements selected from the group consisting of Ti, V, Mo, and W,
M represents one or more elements selected from the group consisting of unavoidable impurity elements, Al, Cr, Cu, Ga, Ag, and Au,
A represents one or more elements selected from the group consisting of N, C, H, and P,
0≤x≤0.5,
0≤y≤0.7,
4≤a≤20,
b=100−a−c−d,
0<c≤7,
0≤d≤1, and
1≤e≤18.

Assignees

• Toyota Motor Co Ltd

Inventors

• Sakuma Noritsugu
• Kato Akira
• Washio Kota
• Kishimoto Hidefumi
• Yano Masao
• Manabe Akira
• Ito Masaaki
• Suzuki Shunji
• Kobayashi Kurima

Classifications

• H01F1/0593

  of tetragonal ThMn12-structure · CPC title

• C22C38/00

  Ferrous alloys, e.g. steel alloys (cast-iron alloys C22C37/00) · CPC title

• C22C30/02 Primary

  containing copper · CPC title

• C22C30/00

  Alloys containing less than 50% by weight of each constituent · CPC title

• C22C1/02

  by melting {(C22C1/1036 takes precedence)} · CPC title