Hostname: page-component-5c6d5d7d68-qks25 Total loading time: 0 Render date: 2024-08-20T20:07:28.176Z Has data issue: false hasContentIssue false
  • English
  • Français

Oscillations in Interplanar Spacing Vs. sin2ψ a FEM Analysis

Published online by Cambridge University Press:  06 March 2019

I. C. Noyan  and
L. T. Nguyen
I. C. Noyan
Affiliation:
I.B.M. T. J. Watson Research Center P.O. Box 218 Yorktown Heights, N.Y. 10598
L. T. Nguyen
Affiliation:
I.B.M. T. J. Watson Research Center P.O. Box 218 Yorktown Heights, N.Y. 10598
Get access

Abstract

Recent studies indicate that, if the stress/strain field within the irradiated volume in an x-ray stress determination experiment is inhomogeneous, oscillations occur in the interplanar spacing vs. sin2ψ plots. There is, however, little work on the degree of inhomogeneity required to cause a given oscillation, the uniqueness of the stress fields that can cause a given set of oscillations, or the error caused by applying the traditional methods currently in use to oscillatory data.

In this paper, numerical modeling and eiasto-plastic finite element analysis was used to determine the strain fields in the diffracting volume of a polycrystalline sample under load. The elastic strain fields obtained from the analysis were then averaged over the regions that would diffract in an x-ray experiment/and then correlated to x-ray strain data to obtain an idea of the problems described ahove.

Type
III. X-Ray Stress/Strain Determination, Fractography, Diffraction, Line Broadening Analysis
Information
Advances in X-Ray Analysis , Volume 31: Thirty-Sixth Annual Conference on Applications of X-ray Analysis, August 3-7, 1987 , 1987 , pp. 191 - 204
Copyright
Copyright © International Centre for Diffraction Data 1987

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Society of Automotive Engineers, “Residual Stress Measurement by X-Ray Diffraction”, SAE784a, 2nd ed. (1971)Google Scholar
2. Cohen, J.B., Dolle, H., and James, M.R., “Determining Stresses from X-Ray Powder Patterns”, NBS Special Publication 567, 453 (1980).Google Scholar
3. Noyan, L. C., “Equilibrium Conditions for the Average Stresses Measured by X-Rays”, Met. Trans. A , 14A, 1907 (1983).Google Scholar
4. Dolle, H. and Hauk, V., “System of Possible LaLtice Strain Distributions on Mechanically Loaded Metallic Materials (in German)”, Z. Metall., 68, 725 (1977).Google Scholar
5. Hank, V., “Evaluation of Macro and Micro-Residual Stresses on Textured Materials by X-Ray, Neutron Diffraction and Deflection Measurements”, Adv. in X-Ray Anal ,29, 17 (1986)Google Scholar
6. Noyau, I.C., “Determination of the Elastic Constants of Inhomogeneous Materials with X-Ray Diffraction”, Mat. Sci. and Eng., 75, 95 (1985).Google Scholar
7. Marion, R.H. and Cohen, J.B., “Anomalies in Measurement of Residual Stress by X-Ray Diffraction”, Adv. in X-Ray Anal., 27, 159 (1984).Google Scholar
8. Lode, W. and Peiter, A., “Numerical X-Ray Residual Stress Analysis of Near Surface Layers (in German)”, Hart. Tech. Mitt., 32, 2355 (1977).Google Scholar
9. Nagashima, S., Shiratori, M., and Nakagawa, R., “Estimation of X-Ray Elastic Modulus in Steel Sheets”, Adv. in X-Ray Anal., 29, 21 (1986).Google Scholar