Compaction and sintering behaviors of a Nd-Fe-B permanent magnet alloy

Journal Article · Tue Nov 15 00:00:00 EST 1988 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.342326· OSTI ID:7017769

Chin, T; Hung, M; Tsai, D; Wu, K; Chang, W

Extensive x-ray diffraction (XRD) and magnetic measurements were done on Nd/sub 15/ Fe/sub 77/ B/sub 8/ magnet alloy green compacts after cold isostatic pressing following a pulsed 2-T field (CIP) and die-pressing under a static 1.2-T perpendicular field (DP1) or parallel field (DP2), and on those after sintering. An alignment factor F, through the calculation of the integrated diffraction intensity ratio of the XRD patterns, was adopted as the effectiveness of magnetic alignment. At the green compact state, DP1 has the best alignment while CIP the worst. However, after sintering the alignment factor was such that CIP>DPI>DP2, the same order as the magnetic properties. Three mechanisms were proposed for the evolution of the alignment factor at different stages of sintering, i.e., that both the appearance of a liquid phase at low temperatures and preferred grain growth at high temperatures enhance F, while recrystallization at intermediate temperatures deteriorates F. CIP results in less-defect green compact, hence less recrystallization, leading to better resultant alignment

• Research Organization: Department of Materials Science and Engineering, Tsing-Hua University, Taiwan, Republic of China
• OSTI ID: 7017769
• Journal Information: J. Appl. Phys.; (United States), Vol. 64:10
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BORON ALLOYS
COMPACTING
MAGNETIC PROPERTIES
SINTERING
IRON ALLOYS
NEODYMIUM ALLOYS
RECRYSTALLIZATION
X-RAY DIFFRACTION
ALLOYS
COHERENT SCATTERING
DIFFRACTION
FABRICATION
PHYSICAL PROPERTIES
RARE EARTH ALLOYS
SCATTERING
360101* - Metals & Alloys- Preparation & Fabrication