A robust and versatile sample preparation technique for the fabrication of cylindrical pillars for imaging by X-ray nano-computed tomography (nano-CT) is presented. The procedure employs simple, cost-effective laser micro-machining coupled with focused-ion beam (FIB) milling, when required, to yield mechanically robust samples at the micrometre length-scale to match the field-of-view (FOV) for nano-CT imaging. A variety of energy and geological materials are exhibited as case studies, demonstrating the procedure can be applied to a variety of materials to provide geometrically optimised samples whose size and shape are tailored to the attenuation coefficients of the constituent phases. The procedure can be implemented for the bespoke preparation of pillars for both lab- and synchrotron-based X-ray nano-CT investigations of a wide range of samples.
A novel way of making samples so that they can be successfully imaged with X‐rays has been developed. This process involves using highly focused lasers to mill away excess material, to leave cylindrical samples ready to be placed in the X‐ray beam. The X‐ray procedure investigated is known as X‐ray computed tomography and is the materials science equivalent of medical CT scanners found in most hospitals. The technique involves rotating the small pillar in the path between a laboratory X‐ray source and a detector, producing a number of images, each similar to a classical bone scan. Using a sophisticated mathematical procedure, these images are reconstructed into a three‐dimensional volume, giving information about the complex microstructure at the nanoscale. This has been applied to materials used for energy generation and a geological sample to illustrate the versatility and robustness of the preparation route.
Keywords: X-ray tomography; laser micro-machining; lithium-ion batteries; sample preparation; shale; solid oxide fuel cells.
© 2017 The Authors. Journal of Microscopy published by John Wiley & Sons Ltd on behalf of Royal Microscopical Society.