TEM studies of the effects of Zr additions on some HDDR- processed, high boron, NdFeB-type powders and hot-pressed magnets

Yi, G., Chapman, J.N., Brown, D.N. and Harrison, I.R. (2000) TEM studies of the effects of Zr additions on some HDDR- processed, high boron, NdFeB-type powders and hot-pressed magnets. Journal of Magnetism and Magnetic Materials, 220(2-3), 115 -123. (doi: 10.1016/S0304-8853(00)00502-3)

Abstract

The transmission electron microscope has been used to study the physical and magnetic microstructures of two HDDR-processed NdFeB-type alloys, one without Zr and the other containing 1.1 at% Zr. Studies were made of the as-produced powders and the solids produced following hot-pressing at 900 degrees C. In the HDDR powders, the principal effects of adding Zr were to reduce the average grain size by approximate to 1/3 and made the grain size distribution more uniform. In the hot-pressed samples, the effect of Zr was more dramatic in that grain growth was very significantly reduced. Zr-containing phases were identified and a simple model, due to Zener, used to provide a plausible explanation of how the small amount of Zr present could stabilise the grain size to approximate to 0.5 mu m. The microstructural results correlated well with measured magnetic properties.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Harrison, Dr Ian
• Authors: Yi, G., Chapman, J.N., Brown, D.N., and Harrison, I.R.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: Journal of Magnetism and Magnetic Materials
• ISSN: 0304-8853