In the present work, through in situ TEM experiments it is found that cyclic loading with low stress amplitude can drive most dislocations out of the submicron sample with virtually little change of the shape. However, simultaneously significant shape change always unexpectedly happens under extremely high monotonic loading to drive the pre-existing dislocations out of the free surfaces. Mechanical annealing has been demonstrated to be an effective method for decreasing the overall dislocation density in submicron single crystal. Buzaré for their help in experiments and in interpretation. Tabary for their contributions in simulation software and J.M. The slight discrepancy for HE data may come either from a unperfect model for the spectrum or from the detector response. The same factor between simulated and experimental data was used on LE and HE data with a good result, especially on LE data. The agreement between experimental and simulated data is good, when we add some correction taking scattering effects inside the detector into account. The agreement between Discussion and conclusionĪ validation of the code was done at two energies and on several kinds of simple objects. 3 shows the scattered profiles across 13 and 23 cm Lucite steps. The experimental edge is not very sharp, probably due to the blur of scattering inside the detector rather than due to misalignement.įig. The uncollided and scattered simulated profiles are also shown. 2 shows the comparison between total experimental and simulated profiles for the first step. We present results on step phantoms only, but similar results are obtained on the plates and the PVC stair.įig. The 2D detector is a digital flat panel Comparison simulation-experimentation on step phantoms The dose delivered by the beam was measured with an ionization chamber. The beam is collimated by a square collimator in order to match the detector size. The tube intensities are 7 and 3 mA, respectively. The LE spectrum is centered on photoelectric energies whereas the HE spectrum is centered on Compton energies for human tissues. The X-ray tube delivers X-ray beams of 70 kV (LE) or 140 kV (HE), with appropriate filters for a good spectrum separation. Section snippets Description of the experiment
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