DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Processing of Alnico Magnets by Additive Manufacturing

Abstract

Permanent magnets without rare earth (RE) elements, such as alnico, will improve supply stability and potentially decrease permanent magnet cost, especially for traction drive motors and other increased temperature applications. Commercial alnico magnets with the highest energy product are produced by directional solidification (DS) to achieve a < 001 > columnar grain orientation followed by significant final machining, adding to the high cost. Additive manufacturing (AM) is an effective method to process near net-shape parts with minimal final machining of complex geometries. AM also, has potential for texture/grain orientation control and compositionally graded structures. This report describes fabrication of alnico magnets by AM using both laser engineered net shaping (LENS)/directed energy deposition (DED) and electron beam melting powder bed fusion (EBM/PBF). High pressure gas atomized (HPGA) pre-alloyed alnico powders, with high purity and sphericity, were built into cylindrical and rectangular samples, followed by magnetic annealing (MA) and a full heat treatment (FHT). The magnetic properties of these AM processed specimens were different from their cast and sintered counterparts of the same composition and show a great sensitivity to heat treatment. The AM process parameters used in this developmental study did not yet result in any preferred texture within the alnicomore » AM builds. These findings demonstrate feasibility for near net-shape processing of alnico permanent magnets for use in next generation traction drive motors and other applications requiring increased operating temperatures and/or complex engineered part geometries, especially with further AM process development for texture control.« less

Authors:
ORCiD logo [1];  [2]; ORCiD logo [1];  [3];  [3];  [3];  [4]
  1. Ames Lab., Ames, IA (United States)
  2. Iowa State Univ., Ames, IA (United States)
  3. North Carolina State Univ., Raleigh, NC (United States)
  4. Ames Lab., Ames, IA (United States); Iowa State Univ., Ames, IA (United States)
Publication Date:
Research Org.:
Ames Lab., Ames, IA (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
OSTI Identifier:
1577119
Report Number(s):
IS-J-10086
Journal ID: ISSN 2076-3417; ASPCC7
Grant/Contract Number:  
AC02-07CH11358
Resource Type:
Accepted Manuscript
Journal Name:
Applied Sciences
Additional Journal Information:
Journal Volume: 9; Journal Issue: 22; Journal ID: ISSN 2076-3417
Publisher:
MDPI
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; additive manufacturing; permanent magnets; alnico

Citation Formats

White, Emma, Rinko, Emily, Prost, Timothy, Horn, Timothy, Ledford, Christopher, Rock, Christopher, and Anderson, Iver. Processing of Alnico Magnets by Additive Manufacturing. United States: N. p., 2019. Web. doi:10.3390/app9224843.
White, Emma, Rinko, Emily, Prost, Timothy, Horn, Timothy, Ledford, Christopher, Rock, Christopher, & Anderson, Iver. Processing of Alnico Magnets by Additive Manufacturing. United States. https://doi.org/10.3390/app9224843
White, Emma, Rinko, Emily, Prost, Timothy, Horn, Timothy, Ledford, Christopher, Rock, Christopher, and Anderson, Iver. Tue . "Processing of Alnico Magnets by Additive Manufacturing". United States. https://doi.org/10.3390/app9224843. https://www.osti.gov/servlets/purl/1577119.
@article{osti_1577119,
title = {Processing of Alnico Magnets by Additive Manufacturing},
author = {White, Emma and Rinko, Emily and Prost, Timothy and Horn, Timothy and Ledford, Christopher and Rock, Christopher and Anderson, Iver},
abstractNote = {Permanent magnets without rare earth (RE) elements, such as alnico, will improve supply stability and potentially decrease permanent magnet cost, especially for traction drive motors and other increased temperature applications. Commercial alnico magnets with the highest energy product are produced by directional solidification (DS) to achieve a < 001 > columnar grain orientation followed by significant final machining, adding to the high cost. Additive manufacturing (AM) is an effective method to process near net-shape parts with minimal final machining of complex geometries. AM also, has potential for texture/grain orientation control and compositionally graded structures. This report describes fabrication of alnico magnets by AM using both laser engineered net shaping (LENS)/directed energy deposition (DED) and electron beam melting powder bed fusion (EBM/PBF). High pressure gas atomized (HPGA) pre-alloyed alnico powders, with high purity and sphericity, were built into cylindrical and rectangular samples, followed by magnetic annealing (MA) and a full heat treatment (FHT). The magnetic properties of these AM processed specimens were different from their cast and sintered counterparts of the same composition and show a great sensitivity to heat treatment. The AM process parameters used in this developmental study did not yet result in any preferred texture within the alnico AM builds. These findings demonstrate feasibility for near net-shape processing of alnico permanent magnets for use in next generation traction drive motors and other applications requiring increased operating temperatures and/or complex engineered part geometries, especially with further AM process development for texture control.},
doi = {10.3390/app9224843},
journal = {Applied Sciences},
number = 22,
volume = 9,
place = {United States},
year = {Tue Nov 12 00:00:00 EST 2019},
month = {Tue Nov 12 00:00:00 EST 2019}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 13 works
Citation information provided by
Web of Science

Save / Share:

Works referenced in this record:

Contribution to the study of alpha-sub-gamma phase in alnico 8 alloys
journal, May 1982


Alpha‐Sub‐Gamma Phase in Alnico 8 Alloys
journal, March 1965

  • Julien, C. A.; Jones, F. G.
  • Journal of Applied Physics, Vol. 36, Issue 3
  • DOI: 10.1063/1.1714155

Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets
journal, October 2016

  • Li, Ling; Tirado, Angelica; Nlebedim, I. C.
  • Scientific Reports, Vol. 6, Issue 1
  • DOI: 10.1038/srep36212

Fracture toughness studies in sintered SmCo5 magnets
journal, April 2015


Binder Jetting: A Novel NdFeB Bonded Magnet Fabrication Process
journal, April 2016


Recent Developments in High‐Energy Alnico Alloys
journal, March 1966

  • Cronk, Edward R.
  • Journal of Applied Physics, Vol. 37, Issue 3
  • DOI: 10.1063/1.1708350

Role of the Applied Magnetic Field on the Microstructural Evolution in Alnico 8 Alloys
journal, January 2014

  • Zhou, Lin; Miller, M. K.; Dillon, H.
  • Metallurgical and Materials Transactions E, Vol. 1, Issue 1
  • DOI: 10.1007/s40553-013-0004-3

Mechanism of Magnetization in Alnico V
journal, October 1950


Intercrystalline Fracture in Alnico 5
journal, March 1966

  • Curran, R. E.; Mendelsohn, L. I.
  • Journal of Applied Physics, Vol. 37, Issue 3
  • DOI: 10.1063/1.1708355

Techniques to Achieve Texture in Permanent Magnet Alloy Systems
journal, March 1965

  • Makino, Noboru; Kimura, Yasuo
  • Journal of Applied Physics, Vol. 36, Issue 3
  • DOI: 10.1063/1.1714162

Theory of Magnetic Properties and Nucleation in Alnico V
journal, March 1950


Microstructure and coercivity in alnico 9
journal, February 2019


Spinodal Decomposition in an Alnico Alloy
journal, July 2016


Simulation of alnico coercivity
journal, July 2017

  • Ke, Liqin; Skomski, Ralph; Hoffmann, Todd D.
  • Applied Physics Letters, Vol. 111, Issue 2
  • DOI: 10.1063/1.4992787

Architecture and magnetism of alnico
journal, August 2014


Novel pre-alloyed powder processing of modified alnico 8: Correlation of microstructure and magnetic properties
journal, May 2015

  • Anderson, I. E.; Kassen, A. G.; White, E. M. H.
  • Journal of Applied Physics, Vol. 117, Issue 17
  • DOI: 10.1063/1.4916996

New Alnico Magnets Fabricated From Pre-Alloyed Gas-Atomized Powder Through Diverse Consolidation Techniques
journal, November 2015


Prospects for Non-Rare Earth Permanent Magnets for Traction Motors and Generators
journal, June 2012


Development of controlled solid-state alignment for alnico permanent magnets in near-final shape
journal, May 2017

  • Anderson, Iver E.; Kassen, Aaron G.; White, Emma M. H.
  • AIP Advances, Vol. 7, Issue 5
  • DOI: 10.1063/1.4973843

Fracture toughness of commercial magnets
journal, January 1996

  • Horton, J. A.; Wright, J. L.; Herchenroeder, J. W.
  • IEEE Transactions on Magnetics, Vol. 32, Issue 5
  • DOI: 10.1109/20.538873

The metallurgy and processing science of metal additive manufacturing
journal, March 2016


Powder bed charging during electron-beam additive manufacturing
journal, February 2017


Site specific control of crystallographic grain orientation through electron beam additive manufacturing
journal, November 2014


Magnetic properties of alnico 5 and alnico 8 phases at the sequential stages of heat treatment in a field
journal, June 1970


Net Shape Processing of Alnico Magnets by Additive Manufacturing
journal, November 2017

  • White, Emma Marie Hamilton; Kassen, Aaron Gregory; Simsek, Emrah
  • IEEE Transactions on Magnetics, Vol. 53, Issue 11
  • DOI: 10.1109/TMAG.2017.2711965

Structure of Alnico V
journal, March 1961

  • Campbell, Robert B.; Julien, Carl A.
  • Journal of Applied Physics, Vol. 32, Issue 3
  • DOI: 10.1063/1.2000397

Simulation of alnico coercivity
text, January 2017