University of Illinois Urbana-Champaign

Radiation-Induced Segregation and Precipitation in Ion-Irradiated Molybdenum-Rhenium Alloys

Erck, Robert Alan

This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.

Permalink

https://hdl.handle.net/2142/71855

Description

Title
Radiation-Induced Segregation and Precipitation in Ion-Irradiated Molybdenum-Rhenium Alloys
Author(s)
Erck, Robert Alan
Issue Date
1988
Doctoral Committee Chair(s)
  • Rehn, Lynn E.,
  • Wayman, C. Marvin
Department of Study
Metallurgy and Mining Engineering
Discipline
Metallurgical Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
  • Engineering, Nuclear
  • Engineering, Metallurgy
  • Engineering, Materials Science
Abstract
  • Radiation-induced solute segregation and precipitation in molybdenum-rhenium solid-solution alloys were studied during elevated-temperature helium- and neon-ion irradiation. Radiation-induced segregation of Re atoms in the same direction as the defect fluxes, that is, toward the external surface, was measured during irradiation by in situ Rutherford backscattering spectrometry (RBS). The results of the segregation measurements were in agreement with theoretical models based on point-defect driven transport of solute atoms toward point-defect sinks.
  • After irradiation, near-surface microstructural changes were studied using transmission-electron microscopy (TEM). Radiation-induced chi-phase precipitates were identified. The precipitates adopted coincident and (111) twin orientations with respect to the matrix. The twinning morphology was explained in terms of a coincident-site-lattice model.
  • The results of the RBS and TEM studies constitute strong evidence that precipitation of the chi phase occurs in Mo-Re solid-solution alloys when radiation-induced solute segregation causes the equilibrium solubility limit to be exceeded near point-defect sinks.
Graduation Semester
1988
Type of Resource
text
Permalink
http://hdl.handle.net/2142/71855

Owning Collections

Graduate Dissertations and Theses at Illinois PRIMARY
Graduate Theses and Dissertations at Illinois
Dissertations and Theses - Metallurgy and Mining Engineering