@inproceedings{2acff0b8f7ba470095071de0cf6d089b,
title = "In situ passivation during high pressure gas atomization of improved MRE2Fe14B for high performance permanent magnet applications",
abstract = "Passivation of RE-containing powder is warranted for large-scale manufacturing of bonded magnets for use in high performance applications. A modified gas atomization chamber allows for a novel approach to in situ passivation of solidified particle surfaces through injection of a reactive gas, nitrogen trifluoride (NF3). The ability to control surface chemistry during processing of fine spherical Rare Earth (RE)-Fe-B powders leads to advantages over current processing methodologies. In particular, the capability to coat particles while {"}in flight{"} may eliminate the need for post atomization treatment, otherwise a necessary step for oxidation and corrosion resistance. Formation of RE-type fluorides on the surface was evidenced through x-ray photoelectron spectroscopy (XPS). Gas fusion analysis on coated powders (dia. <45μm) indicated a reduced oxygen concentration of 580ppm. Thermogravimetric analysis (TGA) revealed a decreased rate of oxidation at elevated temperatures up to 300°C.",
keywords = "Atomization, Bonded permanent magnets, Surface passivation, X-ray photoelectron spectroscopy",
author = "Sokolowski, {P. K.} and Anderson, {I. E.} and W. Tang and Wu, {Y. Q.} and Dennis, {K. W.} and Kramer, {M. J.} and McCallum, {R. W.}",
year = "2007",
language = "English",
isbn = "9780873396776",
series = "TMS Annual Meeting",
pages = "7--17",
booktitle = "8th Global Innovations Symposium",
note = "136th TMS Annual Meeting, 2007 ; Conference date: 25-02-2007 Through 01-03-2007",
}