Nanoscale segregation behavior and high-temperature stability of nanocrystalline W-20 at.% Ti

Nanocrystalline W powders with ∼20 nm average grain size are produced by high-energy ball milling and exposed to a target consolidation temperature of 1100 °C. After 1 week, unalloyed W exhibits substantial grain growth, whereas a W alloy with 20 at.% Ti retains its nanoscale structure. A heterogene...

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Bibliographic Details
Main Authors: Chookajorn, Tongjai (Contributor), Schuh, Christopher A (Contributor)
Other Authors: Massachusetts Institute of Technology. Department of Materials Science and Engineering (Contributor)
Format: Article
Language:English
Published: Elsevier, 2016-11-22T16:09:13Z.
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Online Access:Get fulltext
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100 1 0 |a Chookajorn, Tongjai  |e author 
100 1 0 |a Massachusetts Institute of Technology. Department of Materials Science and Engineering  |e contributor 
100 1 0 |a Schuh, Christopher A  |e contributor 
100 1 0 |a Chookajorn, Tongjai  |e contributor 
100 1 0 |a Schuh, Christopher A  |e contributor 
700 1 0 |a Schuh, Christopher A  |e author 
245 0 0 |a Nanoscale segregation behavior and high-temperature stability of nanocrystalline W-20 at.% Ti 
260 |b Elsevier,   |c 2016-11-22T16:09:13Z. 
856 |z Get fulltext  |u http://hdl.handle.net/1721.1/105404 
520 |a Nanocrystalline W powders with ∼20 nm average grain size are produced by high-energy ball milling and exposed to a target consolidation temperature of 1100 °C. After 1 week, unalloyed W exhibits substantial grain growth, whereas a W alloy with 20 at.% Ti retains its nanoscale structure. A heterogeneous distribution of Ti is observed by independent characterization methods, including scanning transmission electron microscopy, energy dispersive spectroscopy and atom probe tomography. This heterogeneous solute distribution is different from the expected homogeneous solid solution based on bulk W-Ti phase diagrams. Using a Monte Carlo simulation that includes the possibility of grain boundary segregation and allows grain boundaries as potential equilibrium states, a complex nanoscale structure of Ti around W-rich crystallites is explicitly reproduced. This simulated structure has both grain size and extrema in local Ti content in line with the experimental observations. 
520 |a United States. Defense Threat Reduction Agency (Grant No. HDTRA1-11-1-0062) 
520 |a United States. Army Research Office (Grant No. W911NF-09-1-0422) 
546 |a en_US 
655 7 |a Article 
773 |t Acta Materialia