Authors: VK RAVINDRAN JE SHIELD
Publish Date: 2007/05/10
Volume: 38, Issue: 4, Pages: 732-737
Abstract
In this article we report the microstructural evolution of rapidly solidified SmCo alloys from 4 to 16 at pct Sm We have observed a wide variety of phase formation and microstructures ranging from primary Co dendrite formation to eutectic structures to the formation of the metastable SmCo7 compound In particular we observed nonequilibrium formation of Co along with SmCo7 whose presence caused a decrease in coercivity from ∼10 kOe to 500 Oe Alloying elements reduced the scale of the microstructure effectively offsetting the detrimental effects of the Co phase formation and leading to a recovery of the coercivity The eutectic structure with Co rods surrounded by SmCo7 provides a natural path to nanoscale hard/soft magnetic nanocomposites where control of scale and phase content is criticalThis article is based on a presentation made in the symposium entitled “Phase Transformations in Magnetic Materials” which occurred during the TMS Annual Meeting March 12–16 2006 in San Antonio Texas under the auspices of the Joint TMS/MPMD and ASMIMSCTS Phase Transformations CommitteeThis work was supported by the National Science Foundation under Grant No DMR0305354 and the Nebraska Research Initiative The authors also acknowledge QSPINS funded by the National Science Foundation under Grant No 0213808 for facility support
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