What is 3D X-ray Computed Tomography 3D X-ray Computed Tomography works along the same lines as when a doctor takes an X-ray of a broken bone. However, rather than taking just one 2D X-ray picture, known as a radiograph, hundreds or even thousands of radiographs are taken of the object as it is rotated through 360°. The series of 2D radiographs are then reconstructed into a 3D image using sophisticated software packages coupled with powerful computers. The real advantage of CT lies in the fact that a virtual replica is created where one can slice through the layers of the object to reveal its internal structure, akin to peeling an onion. Further, in some cases one can then follow its structure as it changes over time.
Originally CT was developed in the 1970’s for medical imaging and today it is routinely used in both state and private medical centres for diagnosis purposes, such as for the detection of tumours, etc. Recently, CT has seen an increased use in preventative medicine by the use of body scans as part of a general health check.
Although CT has been around for the last 40 years, it is only in the last 10 years that the technology has seen dramatic changes. These changes have been brought about through the combination of massively increased computing power that can handle the huge volumes of data which are produced and the driving force from technological innovation in a number of related fields. These changes have resulted in the capability to perform rapid CT scanning of objects from live biological specimens to the non-destructive testing of aircraft parts, for example.
CT has a number of advantages over traditional materials analysis techniques such as Scanning Electron Microscopy (SEM) or 3D laser scanning. These include:
The Manchester X-ray Imaging Facility (MXIF) is a unique facility that provides both academic and industrial researchers with access to a unique suite of world-class equipment for non-destructive 3D imaging. We are able to analyse almost any sample from a metre in size down to spatial resolutions from one millimetre to 50nm, and have a suite of powerful workstations for the reconstruction, visualisation and quantitative analysis of the data. The facility provides openly available access to the widest range of differently configured laboratory CT systems in the UK. This capability is further augmented by access to Manchester-Diamond nano-tomography synchrotron X-ray beam line at the Diamond light Source, Oxfordshire. The MXIF complements and extends the capabilities that already exist within the School of Materials, and our reserachers are collaborating withr easearchers from many other fields, both at the University of Manchester,and beyond.
Today a number of large technologically driven organisations make use of CT scanning, however few fully utilise the full range of analysis capabilities that is presently possible in terms of length scales and spatial resolution. Within the HMXIF the rapid CT scanning of static specimens and the full 3D reconstruction of data has become a standard procedure and we continue to develop this area of expertise even further through the development of new software, for example.
One of our strengths lies in the use of in-situ environments to study samples under a wide range of conditions from stress corrosion, through elevated temperatures to fatigue loading.