Theses and Dissertations
Issuing Body
Mississippi State University
Advisor
Schneider, Judith A.
Committee Member
Daniewicz, Steven
Committee Member
Newman, James C., Jr.
Committee Member
Smith, Donald M.
Committee Member
McKeighan, Peter
Date of Degree
12-10-2005
Document Type
Graduate Thesis - Open Access
Major
Mechanical Engineering
Degree Name
Master of Science
College
James Worth Bagley College of Engineering
Department
Department of Mechanical Engineering
Abstract
Traditionally, pre-cracking has been performed under tension-tension loading, followed by a load reduction scheme to obtain fatigue crack growth rate data in the near threshold regime. These data have been shown to exhibit load history effects due to remote crack closure. An alternative test method has been developed to minimize these load history effects. This test procedure uses compression pre-cracking to initiate a crack, followed by constant amplitude loading to grow the crack to failure. Compression-compression (C-C) loading as a means of forming a starter crack for fatigue crack growth is a relatively new concept. Cracks grown under C-C loading emanate from the notch tip due to a tensile residual stress field formed during the unloading cycle. The subsequent constant amplitude steady-state crack growth is free of load history effects, after crack growth beyond several compressive plastic zone sizes, and therefore will give a better steady-state representation of the near-threshold regime. A more in-depth examination at this phenomenon is performed herein.
URI
https://hdl.handle.net/11668/19172
Recommended Citation
McKnight, Dustin Henry, "The Use of Compression Precracking Constant Amplitude (CPCA) Test Method to Obtain Near-Threshold Fatigue Crack Growth Behavior In AA7075-T7351" (2005). Theses and Dissertations. 4683.
https://scholarsjunction.msstate.edu/td/4683