Nanoclustering in a MA/ODS Ferritic Alloy

Author

Miller, M.K. ; Fu, C.L. ; Liu, C.T. ; Hoelzer, D.T. ; Russell, K.F.

Author_Institution

Div. of Mater. Sci. & Technol., Oak Ridge Nat. Lab., TN

fYear

2006

fDate

38899

Firstpage

505

Lastpage

506

Abstract

A new higher chromium variant of mechanically alloyed (MA) oxide dispersion strengthened (ODS) ferritic alloy, designated 14YWT, has been developed. The microstructures of this alloy have been characterized in the local electrode atom probe from the initial ball milled flakes through the extruded material that was heat treated at up to 1380degC. No nanoclusters were found in the ball milled flakes but some layering of yttrium and oxygen was observed. A high number density of Ti-, Y- and O-enriched nanoclusters was observed in the flakes after a simulated extrusion treatment of 1 h at 850degC. The nanoclusters were also observed after annealing an extruded rod for 1 h at 1380degC and the grain boundaries were found to be enriched in chromium and tungsten. Results of first-principles calculations on oxygen binding energy in the presence of vacancies suggest that the condition for stable nanoclusters is a well-dispersed Y distribution with more Ti than Y

Keywords

annealing; ball milling; binding energy; chromium alloys; extrusion; grain boundaries; iron alloys; nanostructured materials; titanium alloys; tungsten alloys; vacancies (crystal); yttrium compounds; 1 h; 1380 degC; 14YWT alloy flakes; 850 degC; FeCrWTi-Y₂O₃; MA-ODS ferritic alloys; annealing; ball milling; binding energy; extrusion; first-principles calculations; grain boundaries; heat treatment; local electrode atom probe; mechanically alloyed oxide dispersion strengthened ferritic alloy; microstructure; nanoclustering; vacancies; Annealing; Atomic layer deposition; Ball milling; Chromium alloys; Electrodes; Grain boundaries; Microstructure; Probes; Tungsten; Yttrium;

fLanguage

English

Publisher

ieee

Conference_Titel

Vacuum Nanoelectronics Conference, 2006 and the 2006 50th International Field Emission Symposium., IVNC/IFES 2006. Technical Digest. 19th International

Conference_Location

Guilin

Print_ISBN

1-4244-0401-0

Type

conf

DOI

10.1109/IVNC.2006.335298

Filename

4134681