X-ray determination of stress-strain distribution in unnotched C-rings: A link from micro- to macromechanics
✍ Scribed by C.F. Lo; H. Kamide; G.J. Feng; W.E. Mayo; S. Weissmann
- Publisher
- Elsevier Science
- Year
- 1988
- Weight
- 913 KB
- Volume
- 36
- Category
- Article
- ISSN
- 0001-6160
No coin nor oath required. For personal study only.
✦ Synopsis
An alloy 600 C-ring was subjected to various strain levels and the deformation process was monitored by a computer-aided rocking curve analysis (CARCA) of individual grains. Calibration curves were established, relating the average rocking curve halfwidth of the sampled grain population to the prevailing stress and strain. The strain analysis was carried out as a function of the angular position along the periphery of the C-ring for surface layers and layers at different depth distances. Up to C-ring closure at the nominal strain at 3.3%, the induced plastic strains were confined to a surface layer of 30-40 pm in depth, The large strains and strain gradients below the surface were induced in the apex and near apex region. The extent and spread of microdeformation inhomogeneity increased with increased applied strain. At ring closure, some grains exhibited very large plastic strain while others were not affected by the deformation process. No agreement was obtained on the angular strain dependence between experimental observations and theoretical calculations, if upon straining the induced shape changes were not taken into account. Good agreement on the angular strain dependence for the apex and near apex region was achieved between experiment and theory, when shape changes were taken into account by partitioning the C-ring periphery into sectors with varying radii and inserting the experimentally determined values into the calculations.
It was concluded that the CARCA X-ray method can be a very useful research tool in aiding and guiding mathematical modeling of nonlinear inelastic behavior of solids by disclosing important microstructural and micromechanical aspects.
LO et al.: STRESS-STRAIN DISTRIBUTION IN C-RINGS Sektoren mit verlnderlichem Radius aufgeteilt und die experimentell bestimmten Werte in die Rechnungen einbezogen wurden. Aus den Ergebnissen folgt, da5 die CARCA-Rantgenmethode sehr hilfreich sein kann bei der Unterstiitzung und der Planung der mathematischen Modellierung des inelastischen Verhaltens von Festktirpern, indem wichtige mikrostrukturelle und mikromechanische Aspekte aufgedeckt werden.