Title :
Memory of texture during HDDR processing of NdFeB
Author :
Gutfleisch, O. ; Khlopkov, K. ; Teresiak, A. ; Muller, K.H. ; Drazic, G. ; Mishima, C. ; Honkura, Y.
Author_Institution :
Inst. for Metallic Mater., IFW, Dresden, Germany
fDate :
March 30 2003-April 3 2003
Abstract :
In this paper, we describes the mechanism of texture generation in the recombined powder. Here Nd/sub 12.5/Fe/sub bal/B/sub 6.3/ and Nd/sub 12.5/Fe/sub bal/Ga/sub 0.3/Nb/sub 0.3/B/sub 6.3/ alloys have been HDDR processed and hydrogen partial pressures and dwell times during disproportionation and recombination have been varied systematically. The effect of these processing parameters on the microstructural and magnetic properties is described. Intermediate processing stages were characterized by XRD employing Rietveld analysis, field emission gun scanning electron microscopy, transmission electron microscopy using EDX and selected area diffraction. The degree of texture in aligned recombined powders has been characterized by magnetic measurements using a VSM and qualitatively by Kerr microscopy. Crystallographic relationships between parent, disproportionated and recombined phases are described.
Keywords :
X-ray chemical analysis; X-ray diffraction; boron alloys; coercive force; crystal microstructure; ferromagnetic materials; field emission electron microscopy; gallium alloys; hydrogenation; iron alloys; magnetic particles; neodymium alloys; niobium alloys; permanent magnets; powder metallurgy; scanning electron microscopy; texture; transmission electron microscopy; EDX; HDDR processing; Kerr microscopy; NdFeB; NdFeGaNbB; Rietveld analysis; X-ray diffraction; XRD; dwell times; energy dispersive X-ray analysis; field emission gun scanning electron microscopy; hydrogen partial pressures; hydrogenation disproportionation desorption recombination process; magnetic measurements; magnetic properties; recombined powders; selected area diffraction; texture generation; transmission electron microscopy; vibrating sample magnetometry; Electron emission; Gallium alloys; Hydrogen; Iron alloys; Neodymium; Niobium alloys; Powders; Scanning electron microscopy; Spontaneous emission; Transmission electron microscopy;
Conference_Titel :
Magnetics Conference, 2003. INTERMAG 2003. IEEE International
Conference_Location :
Boston, MA, USA
Print_ISBN :
0-7803-7647-1
DOI :
10.1109/INTMAG.2003.1230546
