Study of Carbon Influence on Magnetic Properties of Metal Injection Molding Nd-Fe-B Based Magnets

Abstract:

In this work, Metal Injection Molding (MIM) process was applied to manufacture Nd-Fe-B magnets, where carbon residues were quantified. In a separated test, controlled additions of carbon were added prior to sintering in the conventional processing of Nd-Fe-B magnets, aiming to simulate the binder residues with more accuracy. The carbon contents in the sintered magnets were related to final magnetic properties such as remanence and coercivity. It was found that the rare-earth content in the alloy influence the threshold where further additions of carbon will degrade coercivity. This study gives directions on developing binder systems and debinding processes, focusing on reaching adequate carbon levels to maximize final magnetic properties.

• Periodical: Materials Science Forum (Volumes 727-728)
• Pages: 124-129
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.727-728.124
• Online since: August 2012
• Authors: Leonardo Ulian Lopes, Matheus Amorim Carvalho, Rafael Sottili Chaves, Marcel Pittol Trevisan, Paulo A.P. Wendhausen, Hidetoshi Takiishi
• Keywords: Carbon Residues, Metal Injection Molding (MIM), NdFeB Magnet

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