Accession Number : ADA299589

Title :   A Study of the Relationship Between Macroscopic Measures and Physical Processes Occurring During Crack Closure.

Descriptive Note : Final rept.,

Corporate Author : GEORGIA INST OF TECH ATLANTA

Personal Author(s) : Stock, Stuart R. ; Antolovich, Stephen D.

PDF Url : ADA299589

Report Date : 1995

Pagination or Media Count : 46

Abstract : This report is divided into Parts A and B which cover the numerical modeling with supporting fractography and the high resolution x-ray computed tomography of loaded samples, respectively. The figures for each part immediately follow the text of that part. The focus throughout is to relate macroscopic measures of crack closure to the physical-processes occurring at and near the crack tip. The most significant accomplishments of the program detailed in Part A include the following. Roughness-induced crack closure was characterized by fractographic analysis. The crack tip stress parameter, K, was justified as a forcing function at the crack tip in the roughness-induced crack closure problem. Analytical models were developed to predict the closure stress intensity factor as a function of crack length using a "phenomenological approach." The relations between fractographically measured parameters and the crack driving "force" was investigated. (MM)

Descriptors :   *CRACKING(FRACTURING), MATHEMATICAL MODELS, CLOSURES, CRACKS, FRACTOGRAPHY, LITHIUM, ALUMINUM, TOMOGRAPHY, DELAMINATION, FORCE(MECHANICS), GRAIN BOUNDARIES, STRESS CONCENTRATION.

Subject Categories : Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE