Dual phase magnetic material component and method of forming

Patent metadata

Field	Value
Publication number	US-9634549-B2
Application number	US-201314068937-A
Country	US
Kind code	B2
Filing date	Oct 31, 2013
Priority date	Oct 31, 2013
Publication date	Apr 25, 2017
Grant date	Apr 25, 2017

Abstract

A magnetic component having intermixed first and second regions, and a method of preparing that magnetic component are disclosed. The first region includes a magnetic phase and the second region includes a non-magnetic phase. The method includes mechanically masking pre-selected sections of a surface portion of the component by using a nitrogen stop-off material and heat-treating the component in a nitrogen-rich atmosphere at a temperature greater than about 900° C. Both the first and second regions are substantially free of carbon, or contain only limited amounts of carbon; and the second region includes greater than about 0.1 weight % of nitrogen.

First claim

The invention claimed is:

1. A magnetic component, comprising:
intermixed first and second regions formed from a single material, wherein
(a) the first region comprises a magnetic phase;
(b) the second region comprises a non-magnetic phase;
(c) a concentration of carbon in both the first and second regions is zero or less than about 0.05 weight %; and
(d) the second region comprises greater than about 0.1 weight % of nitrogen.

2. The component of claim 1 , wherein the component comprises a surface portion and an interior portion, and the intermixed first and second regions are present in both the surface and interior portions.

3. The component of claim 2 , wherein a volume % of the second region in the interior portion is equal to or greater than the volume % of the second region in the surface portion.

4. The component of claim 1 , wherein the component has a thickness in a range from about 0.1 mm to about 5 mm.

5. The component of claim 4 , wherein the component comprises a surface portion, and the width of the second region at the surface portion is greater than about 0.5 mm.

6. The component of claim 1 , wherein at least one of the first and second regions has an interconnected geometry.

7. The component of claim 1 , wherein a volume % of the first region in the component is greater than the volume % of the second region.

8. The component of claim 1 , wherein the second region comprises greater than about 0.4 weight % of nitrogen.

9. The component of claim 1 , wherein the first and second regions are free of carbon.

10. A synchronous reluctance machine, comprising the magnetic component of claim 1 .

Assignees

• Gen Electric

Inventors

• Dial Laura Cerully
• Didomizio Richard
• Johnson Francis

Classifications

• C21D2221/00

  Treating localised areas of an article · CPC title

• C21D1/06

  Surface hardening · CPC title

• C21D1/26

  Methods of annealing · CPC title

• C21D9/00

  Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor · CPC title

• C23C8/26

  of ferrous surfaces · CPC title