Accession Number : ADA132365

Title :   Determining Stresses in the Presence of Nonlinearities in Interplanar Spacing vs. SIN Squared PSI.

Descriptive Note : Technical rept.,

Corporate Author : NORTHWESTERN UNIV EVANSTON IL DEPT OF MATERIALS SCIENCE

Personal Author(s) : Noyan,I C ; Cohen,J B

PDF Url : ADA132365

Report Date : 29 Jul 1983

Pagination or Media Count : 23

Abstract : The physical meaning of non-linearities in d vs. sin sub 2 psi lines, encountered in X-ray measurements of surface residual stresses in polycrystalline materials is investigated. It is shown that when oscillations are present in any one reflection, switching to another reflection to obtain a straight line in d vs. sin sub 2 psi is feasible only under very special conditions. The authors also discuss the effect of quasi-homogeneous strain distributions and investigate the effects of psi-range on the accuracy of X-ray residual stress measurements when psi-splitting is present. A new geometric error is also discussed that can not be detected by the annealed powder method often used for alignment.

Descriptors :   *Residual stress, *Materials, *Equations, *Polycrystalline, *X rays, Measurement, Nonlinear systems, Surfaces, Oscillation, Reflection, Stress strain relations, Accuracy, Splitting, Errors, Geometry, Annealing, Powders

Subject Categories : Miscellaneous Materials
      Theoretical Mathematics
      Crystallography
      Optics
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE