An ultrasonic study of trapped hydrogen in niobium
Huang, Kai-Feng
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/2142/25397
Description
Title
An ultrasonic study of trapped hydrogen in niobium
Author(s)
Huang, Kai-Feng
Issue Date
1982
Doctoral Committee Chair(s)
Granato, A.V.
Department of Study
Physics
Discipline
Physics
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
trapped hydrogen
niobium
interstitial oxygen
BCC metals
Language
en
Abstract
The purpose of the present work is to establish a model for the configuration of hydrogen trapped at interstitial oxygen or nitrogen impurities in BCC metals. Such a model would 'be important for an understanding of the physical properties of such systems, particularly of the quantum diffusion effects which occur.
A review of all the available data (specific heat, internal friction, neutron scattering, channeling, thermal conductivity) on Nb-O-H or Nb-N-H systems, is first given. By reexamining the data for clues, an eight-state tunnelling model is proposed, and the properties of the system are developed. A comparison of the predictions of this model with the data is given, and the four parameters that describe the model are determined. A simple potential calculation is also performed to demonstrate the qualitative features of the model.
Measurements have been made of ultrasonic attenuation and velocity in the Nb-O-H system as a function of temperature, frequency, polarization and isotope. In addition to the previously found stable peak, an additional peak is found when the specimen is cooled rapidly. The peak anneals at the same temperature as those found by Hanada in their resistivity quenching experiments, indicating that the quenched-in defect is an OH2 complex. An extension of the model described in Part A is given to account for the relaxation.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
