Investigation Of 3d-Shell Electrons And Hyperfine Interaction In Nd-Fe-B Magnetic Materials

Coincidence Doppler broadening spectrum, lifetime spectrum and Mossbauer spectrum measurements have been performed in pure Fe, as-cast and ball-milled binary Nd-Fe alloys and ternary Nd-Fe-B alloys.(1) In analyzing the coincidence Doppler broadening spectra of binary Nd-Fe alloys, the 3d electron signal for binary Nd-Fe alloys can be extracted. The experimental results show that the height of the peak in the ratio curve of binary Nd-Fe alloys decreases with the increasing of the content of Nd in totally, however, there is an abnormal rising up at Nd_10.5Fe_89.5.(2) In analyzing the coincidence Doppler broadening spectra of ternary Nd-Fe-B alloys, it has been found that the height of the peak in the ratio curve of ternary Nd-Fe-B alloys decreases with the increasing of the content of Nd in totally, however, there is also an abnormal rising up at Nd₁₂Fe₈₂B₆.(3) The peak in the ratio curve of ternary Nd-Fe-B alloy is lower than that of binary Nd-Fe alloy with the same content of Nd.(4) The values of Isomer shift for binary Nd-Fe and ternary Nd-Fe-B alloys are negative.(5) The Quadrupole Splitting of ball-milled binary Nd-Fe powder is smaller than that of as-cast binary Nd-Fe alloys with the same chemical composition.(6) In the case of binary Nd-Fe alloy, as the Nd content less than 12at%, the hyperfine field (B_hf) of ball-milled binary Nd-Fe powder is larger than that of as-cast Nd-Fe alloys with the same chemical composition. However, as the Nd content higher than 12at%, the hyperfine field (B_hf) of ball-milled binary Nd-Fe powder is less than that of as-cast Nd-Fe alloys with the same chemical composition.(7) The hyperfine field (B_hf) of ball-milled ternary Nd-Fe-B powder is larger than that of as-cast ternary Nd-Fe-B alloys with the same chemical composition.