In situ passivation during high pressure gas atomization of improved MRE2Fe14B for high performance permanent magnet applications

P. K. Sokolowski; I. E. Anderson; W. Tang; Y. Q. Wu; K. W. Dennis; M. J. Kramer; R. W. McCallum

In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications

P. K. Sokolowski
, I. E. Anderson
, W. Tang
, Y. Q. Wu
, K. W. Dennis
, M. J. Kramer
, R. W. McCallum

Division of Research and Economic Development

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

2 Scopus citations

Abstract

Passivation of RE-containing powder is warranted for large-scale manufacturing of bonded magnets for use in high performance applications. A modified gas atomization chamber allows for a novel approach to in situ passivation of solidified particle surfaces through injection of a reactive gas, nitrogen trifluoride (NF₃). The ability to control surface chemistry during processing of fine spherical Rare Earth (RE)-Fe-B powders leads to advantages over current processing methodologies. In particular, the capability to coat particles while "in flight" may eliminate the need for post atomization treatment, otherwise a necessary step for oxidation and corrosion resistance. Formation of RE-type fluorides on the surface was evidenced through x-ray photoelectron spectroscopy (XPS). Gas fusion analysis on coated powders (dia. <45μm) indicated a reduced oxygen concentration of 580ppm. Thermogravimetric analysis (TGA) revealed a decreased rate of oxidation at elevated temperatures up to 300°C.

Original language	English
Title of host publication	8th Global Innovations Symposium
Subtitle of host publication	Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting
Pages	7-17
Number of pages	11
State	Published - 2007
Event	136th TMS Annual Meeting, 2007 - Orlando, FL, United States Duration: 25 Feb 2007 → 1 Mar 2007

Publication series

Name	TMS Annual Meeting

Conference

Conference	136th TMS Annual Meeting, 2007
Country/Territory	United States
City	Orlando, FL
Period	25/02/07 → 1/03/07

Keywords

Atomization
Bonded permanent magnets
Surface passivation
X-ray photoelectron spectroscopy

Cite this

Sokolowski, P. K., Anderson, I. E., Tang, W., Wu, Y. Q., Dennis, K. W., Kramer, M. J., & McCallum, R. W. (2007). In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications. In 8th Global Innovations Symposium: Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting (pp. 7-17). (TMS Annual Meeting).

Sokolowski, P. K. ; Anderson, I. E. ; Tang, W. et al. / In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications. 8th Global Innovations Symposium: Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting. 2007. pp. 7-17 (TMS Annual Meeting).

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title = "In situ passivation during high pressure gas atomization of improved MRE2Fe14B for high performance permanent magnet applications",

abstract = "Passivation of RE-containing powder is warranted for large-scale manufacturing of bonded magnets for use in high performance applications. A modified gas atomization chamber allows for a novel approach to in situ passivation of solidified particle surfaces through injection of a reactive gas, nitrogen trifluoride (NF3). The ability to control surface chemistry during processing of fine spherical Rare Earth (RE)-Fe-B powders leads to advantages over current processing methodologies. In particular, the capability to coat particles while {"}in flight{"} may eliminate the need for post atomization treatment, otherwise a necessary step for oxidation and corrosion resistance. Formation of RE-type fluorides on the surface was evidenced through x-ray photoelectron spectroscopy (XPS). Gas fusion analysis on coated powders (dia. <45μm) indicated a reduced oxygen concentration of 580ppm. Thermogravimetric analysis (TGA) revealed a decreased rate of oxidation at elevated temperatures up to 300°C.",

keywords = "Atomization, Bonded permanent magnets, Surface passivation, X-ray photoelectron spectroscopy",

author = "Sokolowski, \{P. K.\} and Anderson, \{I. E.\} and W. Tang and Wu, \{Y. Q.\} and Dennis, \{K. W.\} and Kramer, \{M. J.\} and McCallum, \{R. W.\}",

year = "2007",

language = "English",

isbn = "9780873396776",

series = "TMS Annual Meeting",

pages = "7--17",

booktitle = "8th Global Innovations Symposium",

note = "136th TMS Annual Meeting, 2007 ; Conference date: 25-02-2007 Through 01-03-2007",

}

Sokolowski, PK, Anderson, IE, Tang, W, Wu, YQ, Dennis, KW, Kramer, MJ & McCallum, RW 2007, In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications. in 8th Global Innovations Symposium: Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting. TMS Annual Meeting, pp. 7-17, 136th TMS Annual Meeting, 2007, Orlando, FL, United States, 25/02/07.

In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications. / Sokolowski, P. K.; Anderson, I. E.; Tang, W. et al.
8th Global Innovations Symposium: Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting. 2007. p. 7-17 (TMS Annual Meeting).

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › peer-review

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T1 - In situ passivation during high pressure gas atomization of improved MRE2Fe14B for high performance permanent magnet applications

AU - Sokolowski, P. K.

AU - Anderson, I. E.

AU - Tang, W.

AU - Wu, Y. Q.

AU - Dennis, K. W.

AU - Kramer, M. J.

AU - McCallum, R. W.

PY - 2007

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N2 - Passivation of RE-containing powder is warranted for large-scale manufacturing of bonded magnets for use in high performance applications. A modified gas atomization chamber allows for a novel approach to in situ passivation of solidified particle surfaces through injection of a reactive gas, nitrogen trifluoride (NF3). The ability to control surface chemistry during processing of fine spherical Rare Earth (RE)-Fe-B powders leads to advantages over current processing methodologies. In particular, the capability to coat particles while "in flight" may eliminate the need for post atomization treatment, otherwise a necessary step for oxidation and corrosion resistance. Formation of RE-type fluorides on the surface was evidenced through x-ray photoelectron spectroscopy (XPS). Gas fusion analysis on coated powders (dia. <45μm) indicated a reduced oxygen concentration of 580ppm. Thermogravimetric analysis (TGA) revealed a decreased rate of oxidation at elevated temperatures up to 300°C.

AB - Passivation of RE-containing powder is warranted for large-scale manufacturing of bonded magnets for use in high performance applications. A modified gas atomization chamber allows for a novel approach to in situ passivation of solidified particle surfaces through injection of a reactive gas, nitrogen trifluoride (NF3). The ability to control surface chemistry during processing of fine spherical Rare Earth (RE)-Fe-B powders leads to advantages over current processing methodologies. In particular, the capability to coat particles while "in flight" may eliminate the need for post atomization treatment, otherwise a necessary step for oxidation and corrosion resistance. Formation of RE-type fluorides on the surface was evidenced through x-ray photoelectron spectroscopy (XPS). Gas fusion analysis on coated powders (dia. <45μm) indicated a reduced oxygen concentration of 580ppm. Thermogravimetric analysis (TGA) revealed a decreased rate of oxidation at elevated temperatures up to 300°C.

KW - Atomization

KW - Bonded permanent magnets

KW - Surface passivation

KW - X-ray photoelectron spectroscopy

UR - https://www.scopus.com/pages/publications/40549130692

M3 - Conference contribution

AN - SCOPUS:40549130692

SN - 9780873396776

T3 - TMS Annual Meeting

SP - 7

EP - 17

BT - 8th Global Innovations Symposium

T2 - 136th TMS Annual Meeting, 2007

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Sokolowski PK, Anderson IE, Tang W, Wu YQ, Dennis KW, Kramer MJ et al. In situ passivation during high pressure gas atomization of improved MRE₂Fe₁₄B for high performance permanent magnet applications. In 8th Global Innovations Symposium: Trends in Materials and Manufacturing Technologies for Energy Production 2007 - Proceedings of Symposium held during the 2007 TMS Annual Meeting. 2007. p. 7-17. (TMS Annual Meeting).