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Title: Additive Manufacturing of Near-net Shaped Permanent Magnets

Abstract

The technical objective of this technical collaboration phase I proposal is to fabricate near net-shaped permanent magnets using alloy powders utilizing direct metal deposition technologies at the ORNL MDF. Direct Manufacturing using the POM laser system was used to consolidate Nd 2Fe 14B (NdFeB) magnet powders into near net-shape parts efficiently and with virtually no wasted material as part of the feasibility study. We fabricated builds based on spherical NdFeB magnet particles. The results show that despite the ability to fabricate highly reactive materials in the laser deposition process, the magnetic coercivity and remanence of the NdFeB hard magnets is significantly reduced. X-ray powder diffraction in conjunction with electron microscopy showed that the material experienced a primary Nd 2Fe 17B x solidification due to the undercooling effect (>60K). Consequently the presence of alpha iron phase resulted in deterioration of the build properties. Further optimization of the processing parameters is needed to maintain the Nd 2Fe 14B phase during fabrication.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Chemical Sciences Division
  2. Arnold Magnetic Technologies Corp., Rochester, NY (United States)
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Manufacturing Demonstration Facility (MDF)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Advanced Manufacturing Office (EE-5A)
OSTI Identifier:
1311265
Report Number(s):
ORNL/TM-2016/340
ED2802000; CEED492; CRADA/NFE-15-05476
DOE Contract Number:
AC05-00OR22725
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE

Citation Formats

Paranthaman, M. Parans, Sridharan, Niyanth, List, Fred A., Babu, S. S., Dehoff, Ryan R., and Constantinides, Steve. Additive Manufacturing of Near-net Shaped Permanent Magnets. United States: N. p., 2016. Web. doi:10.2172/1311265.
Paranthaman, M. Parans, Sridharan, Niyanth, List, Fred A., Babu, S. S., Dehoff, Ryan R., & Constantinides, Steve. Additive Manufacturing of Near-net Shaped Permanent Magnets. United States. doi:10.2172/1311265.
Paranthaman, M. Parans, Sridharan, Niyanth, List, Fred A., Babu, S. S., Dehoff, Ryan R., and Constantinides, Steve. 2016. "Additive Manufacturing of Near-net Shaped Permanent Magnets". United States. doi:10.2172/1311265. https://www.osti.gov/servlets/purl/1311265.
@article{osti_1311265,
title = {Additive Manufacturing of Near-net Shaped Permanent Magnets},
author = {Paranthaman, M. Parans and Sridharan, Niyanth and List, Fred A. and Babu, S. S. and Dehoff, Ryan R. and Constantinides, Steve},
abstractNote = {The technical objective of this technical collaboration phase I proposal is to fabricate near net-shaped permanent magnets using alloy powders utilizing direct metal deposition technologies at the ORNL MDF. Direct Manufacturing using the POM laser system was used to consolidate Nd2Fe14B (NdFeB) magnet powders into near net-shape parts efficiently and with virtually no wasted material as part of the feasibility study. We fabricated builds based on spherical NdFeB magnet particles. The results show that despite the ability to fabricate highly reactive materials in the laser deposition process, the magnetic coercivity and remanence of the NdFeB hard magnets is significantly reduced. X-ray powder diffraction in conjunction with electron microscopy showed that the material experienced a primary Nd2Fe17Bx solidification due to the undercooling effect (>60K). Consequently the presence of alpha iron phase resulted in deterioration of the build properties. Further optimization of the processing parameters is needed to maintain the Nd2Fe14B phase during fabrication.},
doi = {10.2172/1311265},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2016,
month = 7
}

Technical Report:

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  • The technical objective of this technical collaboration phase I proposal is to fabricate net shape isotropic NdFeB bonded magnets utilizing additive manufacturing technologies at the ORNL MDF. The goal is to form complex shapes of thermoplastic and/or thermoset bonded magnets without expensive tooling and with minimal wasted material. Two additive manufacturing methods; the binder jet process; and big area additive manufacturing (BAAM) were used. Binder jetting produced magnets with the measured density of the magnet of 3.47 g/cm 3, close to 46% relative to the NdFeB single crystal density of 7.6 g/cm 3 were demonstrated. Magnetic measurements indicate that theremore » is no degradation in the magnetic properties. In addition, BAAM was used to fabricate isotropic near-net-shape NdFeB bonded magnets with magnetic and mechanical properties comparable or better than those of traditional injection molded magnets. The starting polymer magnet composite pellets consist of 65 vol% isotropic NdFeB powder and 35 vol% polyamide (Nylon-12). The density of the final BAAM magnet product reached 4.8 g/cm 3, and the room temperature magnetic properties are: Intrinsic coercivity Hci = 8.65 kOe, Remanence Br = 5.07 kG, and energy product (BH) max = 5.47 MGOe (43.50 kJ/m 3). This study provides a new pathway for preparing near-net shape bonded magnets for various magnetic applications.« less
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