Development Of A Macrostructural Model For Studying The Combined Effects Of Plasticity And Roughness Induced Crack Closure

Author

Justin Mandel Crapps

Issuing Body

Mississippi State University

Advisor

Daniewicz, Steve

Committee Member

Newman Jr, Jim

Committee Member

Myers, Oliver

Committee Member

Luck, Rogelio

Date of Degree

12-10-2010

Document Type

Dissertation - Open Access

Major

Mechanical Engineering

Degree Name

Doctor of Philosophy (Ph.D)

College

James Worth Bagley College of Engineering

Department

Department of Mechanical Engineering

Abstract

A weight function based modified strip-yield model is adapted to include the mode I effects of roughness induced crack closure. The weight function methodology is verified for arbitrary mixed mode loading conditions under load levels experienced in fatigue crack growth. A rough crack geometry is simulated as a sine wave fitted to a sawtooth defined by an asperity angle and period. Additional mode I crack closure due to mode II sliding of crack faces is calculated and incorporated into the strip-yield model by lengthening and shortening the crack face elements. Simulations of fatigue crack growth using the newly developed model are examined via a design and analysis of computer experiments. The effects of model parameters are identified. Combined roughness and plasticity induced crack closure for long cracks is studied.

URI

https://hdl.handle.net/11668/17018

Recommended Citation

Crapps, Justin Mandel, "Development Of A Macrostructural Model For Studying The Combined Effects Of Plasticity And Roughness Induced Crack Closure" (2010). Theses and Dissertations. 1415.
https://scholarsjunction.msstate.edu/td/1415