A viscous-viscoelastic creep model

The creep data of 304 stainless steel at 1100 °F (593 °C) for pure tension, pure torsion, and combined tension and torsion under varying stress history were analyzed. The variable stresses are step changes in stress including complete unloading, reloading, step-up, step-down, and side steps in which one stress component was held constant while the other was increased or decreased. To predict the complex creep behavior under variable stresses of combined tension and torsion, nonlinear constitutive relations were developed and predictions by the theory were compared with the creep data. In the viscous-viscoelastic creep model the total strain was separated into four strain components: elastic, time-independent plastic, time-dependent-recoverable viscoelastic, and time-dependent-nonrecoverable viscous strain. In this project, only the time-dependent creep strain components were analyzed. For variable loading a modified superposition principle was employed to represent the recoverable creep component, and a strain hardening theory was used to predict the non recoverable creep component. The effects of aging were also considered in the creep constitutive relations. Satisfactory agreement was obtained between the creep data for the variable stresses and the theoretical predictions based on the constant stress creep and creep recovery data.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Masters

Discipline thesis:degree_discipline

Mechanical engineering (MU)

Grantor dc:publisher

University of Missouri--Columbia

Year dc:date.issued

1988

Author dc:creator

• Kim, Seungwook

Advisor dc:contributor.advisor

• Cho, Uee Wan

Statement dc:rights

• OpenAccess.

Language dc:language.iso

eng, English

Handle dc:identifier.uri

https://hdl.handle.net/10355/111910

OAI identifier oai:identifier

oai:mospace.umsystem.edu:10355/111910