Abstract
We report for the first time the range of ThMn12-type crystal structure formation in melt-spun Nd-Fe-Mo-Ti ribbons. These materials, which combine the melt-spun microstructure with the favorable intrinsic magnetic properties of the NdFe12−x(Mo,Ti)x phase, are important as precursors to the formation of hard magnetic materials by nitrogen absorption. Alloys with compositions Nd1.15Fe10+xMo2−2xTix (0≤x≤1), which grade the composition smoothly between the two end point alloys Nd1.15Fe10Mo2 and Nd1.15Fe11Ti, were melt spun at quench wheel velocities 5 m/s≤vs≤30 m/s. From x-ray diffraction patterns we construct a phase formation diagram as a function of Ti content x and wheel speed vs. We find that the desired ThMn12 structure is obtained only in ribbons quenched at low vs. At higher speeds, the ribbons quench instead into the disordered TbCu7-type crystal structure. Further, the ThMn12 structure is considerably less stable at the Ti-rich end of the composition range than at the Mo-rich end: for Nd1.15Fe10Mo2, the ThMn12 structure is obtained for vs≤17.5 m/s, whereas in Nd1.15Fe11Ti only ribbons quenched at vs=5 m/s are of the ThMn12 type. Heat treatments of Nd1.15Fe11Ti ribbons melt spun at 30 m/s confirm the relatively difficult formation of the ThMn12 structure type; annealing temperatures in excess of 1000 °C are required to form the ThMn12 crystal structure.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
