U-Pt-Sm-Ba-O chemical pinning centers in Ag-doped Sm123 textured in reduced oxygen

Ravi Persad Sawh, Roy Weinstein, Drew Parks, Noriko Chikumoto, Masato Murakami

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

In the U/n process enriched uranium is admixed to HTS powders, textured and then irradiated with thermal neutrons. Neutrons must penetrate several centimeters for such processing to be successful in textured materials. Bulk Sm123 cannot be U/n processed because thermal neutrons penetrate <1 mm. However, textured Sm123 can still benefit from chemical pinning centers that are formed during U/n processing. Thin or thick films of Sm123 can still be successfully U/n processed. In the present work, powders containing Ag2O + 20 mol% Sm211 + Sm123 + Pt are doped with depleted U, and textured in a 1% oxygen atmosphere. Microstructure studies indicate the presence of small deposits of (U0.5Pt0.5)SmBa2O6, which are double perovskites. Important characteristics of the U-Pt-Sm-Ba-O particles are: (a) average size is 500 nm, (b) distribution is fairly uniform within the Sm123, (c) the number of deposits is proportional to the mass of admixed U (i.e., size is constant for increasing doping levels) (d) U does not substitute into the background Sm123, (e) Ag does not interact with either U or Pt, and (f) there is less coarsening of the U-rich particles when the dwell time of the maximum temperature in the temperature versus time profile is <2 hours. The U-Pt-Sm-Ba-O deposits are strikingly similar to the U-Pt-Y-Ba-O deposits found earlier in U-doped Y123. Tungsten or molybdenum can be used as nonradioactive substitutes for uranium to produce similar double perovskites deposits.

Original languageEnglish
Pages (from-to)3151-3154
Number of pages4
JournalIEEE Transactions on Applied Superconductivity
Volume13
Issue number2 III
DOIs
Publication statusPublished - 2003 Jun
Externally publishedYes

Fingerprint

Deposits
deposits
Oxygen
oxygen
Neutrons
Uranium
perovskites
thermal neutrons
Powders
uranium
substitutes
Tungsten
Molybdenum
dwell
Coarsening
Processing
Thick films
thick films
molybdenum
tungsten

Keywords

  • Critical current density
  • High-temperature superconductors
  • Melt-textured Sm123
  • Pinning centers

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Physics and Astronomy (miscellaneous)

Cite this

U-Pt-Sm-Ba-O chemical pinning centers in Ag-doped Sm123 textured in reduced oxygen. / Sawh, Ravi Persad; Weinstein, Roy; Parks, Drew; Chikumoto, Noriko; Murakami, Masato.

In: IEEE Transactions on Applied Superconductivity, Vol. 13, No. 2 III, 06.2003, p. 3151-3154.

Research output: Contribution to journalArticle

Sawh, Ravi Persad ; Weinstein, Roy ; Parks, Drew ; Chikumoto, Noriko ; Murakami, Masato. / U-Pt-Sm-Ba-O chemical pinning centers in Ag-doped Sm123 textured in reduced oxygen. In: IEEE Transactions on Applied Superconductivity. 2003 ; Vol. 13, No. 2 III. pp. 3151-3154.
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