Effects of quench rate on the microstructure in melt-spun Nd--Fe--B alloys

Journal Article · Mon Apr 01 04:00:00 EST 1991 · Journal of Materials Research; (USA)

DOI:https://doi.org/10.1557/JMR.1991.0724· OSTI ID:5626386

Zaluska, A; Xu, Y; Altounian, Z; Stroem-Olsen, J O ^[1]; Allem, R; L'Esperance, G ^[2]

---

1. Centre for the Physics of Materials and Department of Physics, McGill University, 3600 University Street, Montreal, Quebec, Canada, H3A 2T8 (CA)
2. Ecole Polytechnique, Departement de Genie Physique, P. O. Box 6079, Montreal, Quebec, (Canada), H3C 3A7

Electron microscope studies have shown significant changes in the microstructure of the Nd{sub 14}Fe{sub 80}B{sub 6} melt-spun ribbons, depending on the quenching conditions. The average grain size of about 20 nm near the wheel side, increasing to 500--700 nm near the free side, can be observed for ribbons of the thickness of about 25--30 {mu}m, indicating strong internal variations in quench rate across the ribbon thickness. For low quenching rates different morphologies of the crystalline phase Nd{sub 2}Fe{sub 14}B are observed. Equiaxed grains near the wheel side of the ribbon become columnar grains or even dendritic grains near the free side. Texturing effects in the equiaxed grains are observed only for grains larger than 30 nm and disappear for very large equiaxed grains (about 500 nm), as well as for dendritic structures. Most evident texture is observed in columnar grains, which crystallized with the c-axis perpendicular to the ribbon plane.

• OSTI ID: 5626386
• Journal Information: Journal of Materials Research; (USA), Journal Name: Journal of Materials Research; (USA) Vol. 6:4; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
BORON ALLOYS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
GRAIN SIZE
IRON ALLOYS
MICROSCOPY
MICROSTRUCTURE
NEODYMIUM ALLOYS
QUENCHING
RARE EARTH ALLOYS
SIZE