Comparison of surface and bulk elastic properties using synchrotron radiation diffraction

Abstract

In order to compare bulk and surface elastic coefficients, transmission and reflection measurements have been performed using synchrotron radiation. A pure Ni sample submitted to different levels of stress has been studied. The spectral analysis of the diffracted beam allows us to determine the strain for a given crystalline plane, with a precision in the range of goniometric X-ray analysis. From the strain Mohr circle and the sin² ψ law, the elastic characteristics for each studied crystalline plane can be deduced. We find significant differences between bulk and surface elastic coefficients.

Key Words:

• Transmission and reflection
• Synchrotron radiation
• Elastic constants
• Diffracted beam