IP Library Granted Patent US 7,988,797
Granted Patent B2
US 7,988,797 · App. 12/781,093 · Granted Aug 2, 2011

Nano-composite magnet, quenched alloy for nano-composite magnet, and method for producing them and method for distinguishing them

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,988,797
App. No.
12/781,093
Granted
Aug 2, 2011
Kind
B2
Abstract

A nanocomposite magnet according to the present invention has a composition represented by the general formula: R x Q y M z (Fe 1-m T m ) bal , where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, and T is at least one element selected from the group consisting of Co and Ni. The mole fractions x, y, z and m satisfy the inequalities of 6 at %≦x<10 at %, 10 at %≦y≦17 at %, 0.5 at %≦z≦6 at % and 0≦m≦0.5, respectively. The nanocomposite magnet includes a hard magnetic phase and a soft magnetic phase that are magnetically coupled together. The hard magnetic phase is made of an R 2 Fe 14 B-type compound, and the soft magnetic phase includes an α-Fe phase and a crystalline phase with a Curie temperature of 610° C. to 700° C. (ω phase) as its main phases.

Claims (16)

1. A nanocomposite magnet having a composition represented by the general formula: R x Q y M z (Fe 1-m T m ) bal , where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, T is at least one element selected from the group consisting of Co and Ni, and the mole fractions x, y, z and m satisfy the inequalities of

6 at %≦x<10 at %,

10 at %≦y≦17 at %,

0.5 at %≦z≦6 at % and

0≦m≦0.5, respectively,

the nanocomposite magnet including a hard magnetic phase and a soft magnetic phase that are magnetically coupled together,

wherein the hard magnetic phase is made of an R 2 Fe 14 B-type compound, and

wherein the soft magnetic phase includes an α-Fe phase and an Fe 2 B phase as its main phases.

2. The nanocomposite magnet of claim 1 , wherein 6 at %≦x≦8 at %.

3. A rapidly solidified alloy to make a nanocomposite magnet, the alloy having a composition represented by the general formula: R x Q y M z (Fe 1-m T m ) bal , where R is at least one rare-earth element, Q is at least one element selected from the group consisting of B and C, M is at least one metal element that is selected from the group consisting of Al, Si, Ti, V, Cr, Mn, Cu, Zn, Ga, Zr, Nb, Mo, Ag, Hf, Ta, W, Pt, Au and Pb and that always includes Ti, T is at T is at least one element selected from the group consisting of Co and Ni, and the mole fractions x, y, z and m satisfy the inequalities of

6 at %≦x<10 at %,

10 at %≦y≦17 at %,

0.5 at %≦z≦6 at % and

0≦m≦0.5, respectively,

wherein the rapidly solidified alloy includes an R 2 Fe 14 B-type compound, an α-Fe phase and an Fe 2 B phase.

4. The rapidly solidified alloy of claim 3 , wherein 6 at %≦x≦8 at %.

Assignments (2)
MERGER Recorded May 18, 2010
From: NEOMAX CO., LTD.
To: HITACHI METALS, LTD.
Reel/Frame 024399/0901 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 17, 2010
From: SHIGEMOTO, YASUTAKA; HIROSAWA, SATOSHI; MIYOSHI, TOSHIO
To: NEOMAX CO., LTD.
Reel/Frame 024393/0605 →