Skip to main content
Micro-Computed Tomography beamline (MCT)
BRIGHT Beamlines

Micro-Computed Tomography beamline (MCT)

Capability summary and techniques

The MCT beamline will complement the existing X-ray imaging and tomography capabilities provided by the Imaging and Medical Beamline (IMBL), and will target applications requiring higher (sub-micron) spatial resolution and involving smaller samples (beam size up to 10 mm high × 64 mm wide).  MCT will be a bending-magnet beamline, operating with X-rays in the energy range of 8 to 40 keV.  Monochromatic X-rays will be selected using a double-multilayer monochromator (DMM).  The DMM, will be able to operate with a relatively wide energy bandpass (ΔE/E~3%) in order to increase the integrated flux at the sample position.  The DMM can also be removed from the X-ray beam path, enabling experiments with a high flux, filtered white beam, for studies that require high-speed data acquisition.  The photon-delivery system (PDS) will also house a single-(vertical) bounce mirror (VBM), capable of suppressing harmonic contamination in low-energy monochromatic beams and providing the means to shape the spectrum of filtered white beams on the high-energy side.  The beamline will greatly benefit from novel phase-contrast modalities (such as propagation-based, grating-based and speckle) in addition to conventional absorption-contrast computed tomography.  The beamline will be equipped with a robotic stage for high-throughput automated sample exchange.  A higher-resolution (nano-CT) configuration based on the use of a Fresnel zone plate system will also be available.

The wide variety of experimental configurations, designed in response to the requirements of a diverse user community will be achieved using three different X-ray imaging detector systems.  These will address key issues such as spatial resolution, contrast, field-of-view, frame rate and white-beam compatibility.

In addition to standard “step-and-shoot” and “on-the-fly” modalities for absorption- and phase-contrast X-ray tomography, MCT will provide capabilities for tomosynthesis, laminography, and helical scanning.  It is envisaged that absorption-contrast and propagation-based phase-contrast imaging will be “workhorse” techniques, however the other phase-contrast modalities will be made available for more specialist requirements, such as dark-field imaging.  Rapid two-dimensional imaging of dynamic processes will also be possible, including via various forms of triggering.

Streamlined data collection, processing, reconstruction, segmentation, rendering and analysis protocols and pipelines will be available via innovative software (including specialised algorithms such as for phase retrieval) and high-performance computing infrastructure.

Scientific applications

Anticipated application areas for non-destructive 3D sample characterisation include biomedical and health science, food science, geosciences, materials science, and palaeontology.  A number of sample environmental stages, such as for high temperature and the application of loads, are planned in collaboration with key groups within the user community.

The MCT beamline has been designed in response to the needs of the user community (including industry) for non-destructive structural characterisation of materials down to the sub-micron spatial scale.  Examples of applications include:

  • Studies of failure mechanisms in 3D-printed (additive manufacturing) samples and various alloy systems.  In the case of additive manufacturing samples, it is possible to obtain valuable information on surface morphology as a function of the build direction and the size and complexity of the design;
  • Quantifying micro-porosity (e.g. pore-size distribution, shape, connectivity and tortuosity) in rocks and shales for the petroleum industry.  The use of gaseous contrast media with K-absorption edges accessible to the MCT beamline shows considerable promise as a non-destructive characterisation and high-resolution tool to study gas-diffusion dynamics and important mechanisms at play such as adsorption.  An example of results obtained using IMBL is shown below;

Demonstration of the use of Xe gas as a contrast media for X-ray micro...

Demonstration of the use of Xe gas as a contrast media for X-ray micro-tomography of rock samples: the two X-ray energies used straddle the Xe K-edge.  Significant detail of the micro-porosity is revealed.

From Mayo et al. (2015) Fuel. 154, 167-173.

  • Furthering understanding of structural properties for coal and coke can also be obtained.  For example, changes to the structure of coke as a result of production methodology (such as blast-furnace parameters) can be studied;
  • In situ investigation of bone response under load conditions and tensile testing.  The use of phase-contrast techniques can greatly enhance the information content in X-ray images of bone as shown below (left);
  • Phase contrast can also be especially beneficial in elucidating the presence of fine, low-Z materials in matrix structures, particularly when relatively well-defined edge structure is present - see the example shown below (right);

X-ray phase-contrast images

X-ray phase-contrast images (20 keV monochromatic) collected at the European Synchrotron Radiation Facility (ESRF) undulator beamline ID-22 for: (left) a thin cross-section of a human femur (the smallest features seen are ~5 μm osteocytes) and (right) an ~2 mm thick Al sheet containing ~10 μm diameter graphite fibres (running vertically).

From Stevenson (priv. comm.) and Stevenson et al. (2003) Nucl.Inst.Meth.Phys.Res. B199, 427-435.

  • Characterisation of materials undergoing structural phase transitions in response to temperature or pressure;
  • Observation of the evolution and dynamics for metallic foams;
  • Soft- and hard-tissue studies using relatively low-energy X-rays to enhance contrast for subtle features - see the example shown below;

Tomography data collected for mouse middle-ear samples

Tomography data collected for mouse middle-ear samples  and using a laboratory-based micro-CT system.  Various malformations and defects are revealed.  Particular middle-ear bones that mechanically conduct sound from the tympanic membrane to the cochlea are shown in purple (malleus), green (incus) and red (stapes).

From Carpinelli et al. (2012) Cell Death Dis. 3, e362.

  • Pyrolysis studies for biomass systems;
  • High-resolution investigation of various fibre and yarn systems;
  • Non-destructive characterisation of small fossils, such as those encapsulated in amber.

Technical Information and Specifications

The MCT beamline comprises three hutches centred at approximately 15, 24 and 31 m from the bending-magnet source point; all three are white-beam compatible.  The first hutch (the first optical enclosure) houses the photon-delivery system, including mask, slits, collimator, DMM, VBM, diagnostics and shutters.  The X-ray beam travels in vacuum until it passes through the Be window at the entrance to the second hutch, approximately 20 m from the source.  The second and third hutches constitute the end stations for conducting user experiments.  When the experiments are in the second hutch, a beam stop at the downstream end provides for safe and open access to the third hutch.  When the experiments are in the third hutch, the second hutch is searched and secured.

Each of the experimental end stations house two large, stable optical tables to support experimental equipment.  These tables can be adjusted in height and (for the first end station) tilt, so that a fixed offset is maintained between the table surface and the X-ray beam for any configuration of the DMM and VBM in the photon-delivery system.

The first experimental hutch houses the sample-exchange robot that is fixed on the first experimental table, and will operate with the primary CT sample stage.  Standard, absorption-contrast and propagation-based phase-contrast X-ray imaging and tomography will be routinely performed on this table; however it will also be possible to use the second experimental hutch in cases where a larger field-of-view is required.

MCT tech specs
Schematic showing the first optical table set-up in the first experimental end station.

 

Schematic of MCT

Schematic of the general-purpose CT stage, which can be moved as required.

Fresnel zone plate optics will be housed on the second table in the first experimental hutch for high-resolution (“nano-CT”) studies down to 200 nm spatial resolution.  For these studies, it is necessary for such experiments to straddle both end stations, with the nano-CT detector being located in the second experimental hutch.  The more specialised phase-contrast modalities such as grating-based and speckle imaging will also be set up in the second experimental hutch using the third and fourth experimental tables.  Configurable evacuated flight tubes will be available in order to avoid attenuation and scattering of the X-ray beam in appreciable air paths, especially at lower energies.

Beamline layout

Plan view of MCT
Plan view of the Micro-Computed Tomography beamline layout.

Technical Specifications

View MCT Technical Specifications

Source

Australian Synchrotron bending magnet (1.3 T); critical energy 7.95 keV

Hutches

9-BM1-A (~15 m); 9-BM1-B (~24 m); 9-BM1-C (~31 m)

Energy range

8 – 40 keV (also filtered-white & pink beams available)

Integrated flux

~ 5 x 1016  photons/sec unfiltered after mask* (~ 50 W)

PDS filters

5 paddles, each with 4 filters - incl. C (graphite), C(diamond), Al, Cu, Zr, Rh & Sn

Monochromator (DMM)

3 multilayer stripes: Ru/C & W/B4C with ∆E/E ~ 3% for 8 – 23 keV & 21 – 40 keV; V/B4C with ∆E/E ~ 0.5% for 8 – 25 keV

Mirror (VBM)

Single-bounce vertical, bendable (concave & convex); Rh & Pt stripes

Optical tables

3 m x 1 m (2) & 2 m x 1 m (2); ~300 mm vertical & 15 mrad tilt adjust.; 100 µm & 0.1 mrad resolution

PDS slits

3 sets, low-scatter, white-beam; range 50 mm (H) x 80 mm (V)

Beam size

Max. *2.0 mrad (H) x 0.3 mrad (V) for filtered-white & pink beams - 44 mm (H) x 6.6 mm (V) for sample positioned at 22 m, 64 mm (H) x 9.6 mm (V) at 32 m;

max. 1.6 mrad (H) x 0.3 mrad (V) for monochromatic beam

Sample handling & environments

Robotic stage for automated sample exchange; environments yet to be finalised - likely to start with high-temperature & load cell

Detectors

CMOS- & CCD-based with scintillators & specialised magnifying optics

 

 Beamline Status:

View MCT Beamline Status

1st July 2017

Project started

September 2017

Capital Investment Case endorsed & approved by ANSTO

20th October 2017

First Beamline Advisory Panel (BAP) meeting convened

June 2018

Conceptual Design Report endorsed

27th March 2019

Contract for DMM awarded to Axilon

21st May 2019

Contract for PDS (excl. DMM) awarded to Axilon

June 2019

Technical Design Report completed

25th June 2019

Contract for hutches awarded to Caratelli

November 2019

Lead Scientist & Lead Engineer visit TOMCAT beamline (SLS) & Axilon

12th December 2019

Approval of Final Design Review report for PDS (incl. DMM)

January 2020

2nd Beamline Scientist joins MCT Team

* Plus delay to be determined following resolution of covid-19 related restrictions

*2020

3rd Beamline Scientist to join MCT Team

*2020

Factory Acceptance Test for PDS (incl. DMM)

*2021

Hutches installation complete

*2021

Utilities installation complete

*2021

Site Acceptance Test for PDS (incl. DMM)

*2021

Regulator ARPANSA approval obtained, radiation-safety tests & "first light“

*2021

Hot Commissioning begins, includes expert users

*Q3 2021

First User Experiments; Beamline fully commissioned over the next 12 months

Staff

Dr Prithi Tissa - Project Manager

Dr Andrew Stevenson - Lead Scientist

Dr Benedicta Arhatari - Beamline Scientist

Mr Adam Walsh - Lead Engineer

Mr Tom Fiala - Senior Controls Engineer

Dr Christina Magoulas - Senior Scientific Software Engineer

Mrs Sinem Ozbilgen - Senior Scientific Software Engineer

Miss Emily Griffin - Mechanical CAD Designer

 

Micro-Computed Tomography Beamline Advisory Panel

Dr Sherry Mayo (Chair) - CSIRO

Dr Kaye Morgan - Monash Univ.

Dr Andrew Rider - DST Group

Dr Ian Schipper - Vic. Univ. Wellington, New Zealand

Prof Adrian Sheppard - Australian National Univ.

Prof. Marco Stampanoni - TOMCAT, SLS, Switzerland

Contact

as-mct@ansto.gov.au