Accession Number : ADA309703
Title : Measurement of Strain at Interior Points Using Synchrotron Radiation.
Descriptive Note : Final rept.,
Corporate Author : CONNECTICUT UNIV STORRS DEPT OF MECHANICAL ENGINEERING
Personal Author(s) : Jordan, Eric H. ; Pease, Douglas M.
PDF Url : ADA309703
Report Date : 16 MAY 1996
Pagination or Media Count : 36
Abstract : A method was developed for measuring strain on interior surfaces of optically opaque objects using synchrotron X ray radiation. Images of small markers (20 micron) were recorded before and after straining using the special properties of synchrotron radiation. Strain is determined by measurement of the change in markers spacing using a special electrooptical method. Gage lengths of 100 microns are currently used and the strain resolution is on the order of 100 micro strain. The first generation version of the technique was used to study composite material behavior and some interesting results were obtained. Finite element studies were conducted to show that markers should be at least 5 diameters apart to avoid marker induced stiffening effects. A greatly improved second generation technique was largely developed. Improvements resulted in order of magnitude increase in the area recorded per radiograph and in the speed of processing the results. These improvements were based on the development of a new marker fabrication technology and a redesigned automated marker positioning measurement system. Measurement error and reliability was also improved. The method can be used for samples up to the atomic number of titanium. One additional minor improvement is needed to begin full utilization of the method.
Descriptors : *STRAIN GAGES, *SYNCHROTRON RADIATION, MEASUREMENT, ELECTROOPTICS, COMPOSITE MATERIALS, FINITE ELEMENT ANALYSIS, STIFFENING, X RAYS, RELIABILITY, TITANIUM, MICROMECHANICS.
Subject Categories : Mechanics
Distribution Statement : APPROVED FOR PUBLIC RELEASE