skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Processing of Alnico Magnets by Additive Manufacturing

Journal Article · · Applied Sciences
DOI:https://doi.org/10.3390/app9224843· OSTI ID:1577119
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)

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.

Research Organization:
Ames Lab., Ames, IA (United States)
Sponsoring Organization:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Vehicle Technologies Office (EE-3V)
Grant/Contract Number:
AC02-07CH11358
OSTI ID:
1577119
Report Number(s):
IS-J-10086; ASPCC7
Journal Information:
Applied Sciences, Vol. 9, Issue 22; ISSN 2076-3417
Publisher:
MDPICopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 13 works
Citation information provided by
Web of Science

References (29)

Advances in Characterization of Non-Rare-Earth Permanent Magnets: Exploring Commercial Alnico Grades 5–7 and 9 journal May 2013
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
Big Area Additive Manufacturing of High Performance Bonded NdFeB Magnets journal October 2016
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
Role of the Applied Magnetic Field on the Microstructural Evolution in Alnico 8 Alloys journal January 2014
Mechanism of Magnetization in Alnico V journal October 1950
Microstructural and magnetic property evolution with different heat-treatment conditions in an alnico alloy journal July 2017
Intercrystalline Fracture in Alnico 5 journal March 1966
Techniques to Achieve Texture in Permanent Magnet Alloy Systems journal March 1965
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
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
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
Fracture toughness of commercial magnets journal January 1996
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
Structure of Alnico V journal March 1961
Simulation of alnico coercivity text January 2017