Memory of texture during HDDR processing of NdFeB

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.

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