3D visualization of defects and microstructural features with laboratory-scale X-ray tomography apparatuses

In the present study, various microstructural features, such as particles and pores, have been visualized in cast and wrought aluminum alloys by employing X-ray tomography apparatuses with a wide range of spatial resolution. Special care is dedicated to evaluate an identical sample for each entire series of imaging experiments. The X-ray tomography apparatuses used include the one performed at a synchrotron radiation facility, which has a spatial resolution level close to the theoretical limit of the projection-type imaging, in addition to two industrial apparatuses. It has been shown that even if industrial apparatuses, which inevitably possess limited spatial resolution levels, are used, the real size and fraction of microstructural features can be estimated by performing imaging experiments above a certain spatial resolution level. It would be, so far as the authors are aware, the first time to demonstrate the feasibility of laboratory-scale X-ray tomography imaging in microstructural observation in a systematic manner, especially focusing on spatial resolution and quantitative capability.