Accession Number : ADA256587


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


Descriptive Note : Annual rept.


Corporate Author : GEORGIA INST OF TECH ATLANTA


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


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a256587.pdf


Report Date : 08 Oct 1991


Pagination or Media Count : 31


Abstract : Activity centered on the development and implementation of robust methods for measuring crack opening in the samples studied with X-ray Tomographic Microscopy (XTM). The existing XTM data of notched tensile (NT) samples consists of a three-dimensional stack of several hundred two-dimensional slices, each containing between 400x400 and 600x600 pixels. Analysis of the three-dimensional crack wandering through this volume in done in several steps. The first step is to determine the separation between crack faces using cuts perpendicular to the stack of slices. Separation will be measured as a function of position for the different applied loads. Cuts parallel to the load axis are expected to give a more precise measure of crack opening than measurements within planes parallel to the slices, especially when the openings are on the order of one or two pixels in size.


Descriptors :   *NONDESTRUCTIVE TESTING , *FRACTURE(MECHANICS) , *CRACK PROPAGATION , MEASUREMENT , ALUMINUM ALLOYS , FRACTOGRAPHY , TOMOGRAPHY , FATIGUE(MECHANICS) , LITHIUM , MICROSCOPY , INTERACTIONS , CLOSURES


Subject Categories : Metallurgy and Metallography
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE