• Vol 7, No 3 (2016)
  • Metalurgy and Material Engineering

Effects of Water Quenching Before Hydrogenation, Disproportionation, Desorption, and Recombination Process on the Magnetic Properties of Nd-Fe-B Powder

Sri Bimo Pratomo, Yongjin Kim, Djoko Hadi Prajitno

Corresponding email: bimo_bblm@yahoo.com


Published at : 29 Apr 2016
IJtech : IJtech Vol 7, No 3 (2016)
DOI : https://doi.org/10.14716/ijtech.v7i3.2785

Cite this article as:

Pratomo, S.B., Kim, Y., Prajitno, D.H., 2016. Effects of Water Quenching Before Hydrogenation, Disproportionation, Desorption, and Recombination Process on the Magnetic Properties of Nd-Fe-B Powder. International Journal of Technology. Volume 7(3), pp.471-478

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Sri Bimo Pratomo Metal Industries Development Center, Jalan Sangkuriang 12, Bandung 40135, Indonesia 2Korea Institute of Materials Science, Changwon, South Korea
Yongjin Kim Metal Industries Development Center, Jalan Sangkuriang 12, Bandung 40135, Indonesia 2Korea Institute of Materials Science, Changwon, South Korea
Djoko Hadi Prajitno Metal Industries Development Center, Jalan Sangkuriang 12, Bandung 40135, Indonesia 2Korea Institute of Materials Science, Changwon, South Korea
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Abstract
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In general, the Nd-Fe-B as-cast ingot is homogenized for a long time before the hydrogenation, disproportionation, desorption and recombination (HDDR) process, to produce good magnetic properties. Since the homogenizing process is expensive, this work examined the possibility of replacing it with a water quenching process for Nd-Fe-B magnetic powder. The magnetic powders were soaked at 1100oC for 4 hours, followed by water quenching prior to HDDR. The resulting powder had magnetic properties that were almost similar to magnetic powder that was homogenized prior to HDDR. The remanence values of the water-quenched alloy and the homogenized alloy were 7.8 KG and 8.9 KG, respectively, while the coercivity values were 12.6 KOe and 10.3 KOe, respectively. In general, the magnetic properties of both samples were not much different. The microstructure of Nd2Fe14B phase combined with a very slight Nd rich phase in micro grain boundary likely caused the coercivity enhancement.

Coercivity, Homogeneizing, HDDR, Water quenching

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