Full field strain measurement in welds
By:  Franklin Thompson Duvall
Publisher: Available from National Technical Information Service
Published: 1998
Place of publication: Springfield, Va
Language: eng
Number of pages: 66
Description: The intent of this study is to examine the stress-strain response of small material subsets in a weld subjected to      some nominal loading using a full- field surface strain mapping technique. This process makes use of the digital      image correlation program (VIC_2D) developed by the University of South Carolina. Full-Field surface strain      mapping will be used to help determine the basic material properties of the various regions within a weld, which      are the heat-affected zone and the mechanically affected zone (weld nugget). During development of this      process, various specimens were tested to verify the accuracy of the strain mapping procedure. A tapered      stainless steel tensile specimen was studied and the results verified by a finite element model of the test      specimen. The results from the full-field strain mapping matched very closely with the strain distribution      predicted by the finite element model. To further prove the validity of the strain mapping process, a .0135 inch      diameter hole was drilled in a 5454-0 aluminum tensile specimen. The strain measurement process detected the      perturbations in the strain field caused by the defect at displacements as low as three-hundredths of an inch      within the three-inch gage length. Furthermore, the strain measured near the edge of the specimen using the      mapping technique matched to within .01 % the strain measured by an extensometer attached to the test      specimen.
Notes: Thesis (M.S. in Mechanical Engineering) College of Engineering, University of South Carolina, 1998.

Includes bibliographical references (leaves 39-40).

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dk/dk cc:9116 1/21/99