The Changes in The Compressive and Tensile Yield Strengths During Uniaxial Cyclic Loading
Tuegel, Eric John
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/2142/70118
Description
Title
The Changes in The Compressive and Tensile Yield Strengths During Uniaxial Cyclic Loading
Author(s)
Tuegel, Eric John
Issue Date
1983
Department of Study
Mechanical Engineering
Discipline
Mechanical Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Applied Mechanics
Abstract
Many of the multiaxial unified-creep plasticity theories which have been proposed as a means to improve design at elevated temperatures have suffered from the drawback that the manner in which the state variables change is difficult to measure. A unified creep-plasticity theory for uniaxial loading which uses the yield strengths in tension, Y(,1), and compression, Y(,2), as the state variables is investigated as the means of improving the formulation of such theories. The yield strengths are easily measured and can be readily transformed to the state variables commonly used in the multiaxial theories.
The yield strengths were measured during a completely reversed cyclic strain amplitude history for 304 stainless steel at 23(DEGREES)C and 600(DEGREES)C, and for Inconel 751 at 788(DEGREES)C and 927(DEGREES)C. The data from these experiments were then plotted in the (Y(,1),Y(,2)) plane and a geometric model of how the state variables change during loading was constructed.
The model clearly demonstrates that on each loading reversal kinematic hardening is the predominate type of hardening. The observed limit cycle behavior of the state variables requires that there be an isotropic softening, or decrease in the elastic range, at the beginning of each reversal. This is followed by a rapid isotropic hardening at the end of the reversal. However, this behavior was obscured by the scatter in the data which was on the order of 10 percent of the elastic range.
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.
