Large volume serial section tomography by Xe Plasma FIB dual beam microscopy

Abstract

Ga(+) Focused Ion Beam-Scanning Electron Microscopes (FIB-SEM) have revolutionised the level of microstructural information that can be recovered in 3D by block face serial section tomography (SST), as well as enabling the site-specific removal of smaller regions for subsequent transmission electron microscope (TEM) examination. However, Ga(+) FIB material removal rates limit the volumes and depths that can be probed to dimensions in the tens of microns range. Emerging Xe(+) Plasma Focused Ion Beam-Scanning Electron Microscope (PFIB-SEM) systems promise faster removal rates. Here we examine the potential of the method for large volume serial section tomography as applied to bainitic steel and WC-Co hard metals. Our studies demonstrate that with careful control of milling parameters precise automated serial sectioning can be achieved with low levels of milling artefacts at removal rates some 60× faster. Volumes that are hundreds of microns in dimension have been collected using fully automated SST routines in feasible timescales (<24h) showing good grain orientation contrast and capturing microstructural features at the tens of nanometres to the tens of microns scale. Accompanying electron back scattered diffraction (EBSD) maps show high indexing rates suggesting low levels of surface damage. Further, under high current Ga(+) FIB milling WC-Co is prone to amorphisation of WC surface layers and phase transformation of the Co phase, neither of which have been observed at PFIB currents as high as 60nA at 30kV. Xe(+) PFIB dual beam microscopes promise to radically extend our capability for 3D tomography, 3D EDX, 3D EBSD as well as correlative tomography.

Time‐lapse lab‐based x‐ray nano‐CT study of corrosion damage

“…These results are consistent with the similar study of leaching behaviour of SAPP in the coating, which showed a much higher dissolution rate of strontium‐rich particles comparing with aluminium‐rich particles (Emad et al ., , Liu et al ., ). The bias and variance of the nano‐CT measurements were estimated using the SIMEX technique (Bradley, ). It was found that noise in the scan data led to the volume fractions being underestimated (negatively biased) by a relatively small amount (<0.5%), although the standard deviations were estimated to be much smaller at <0.01%.…”

Nano-Tomography of Porous Geological Materials Using Focused Ion Beam-Scanning Electron Microscopy

“…Nano-tomography applied through the use of FIB-SEM microscopes is a powerful analytical tool that is being increasingly applied to biological [81], material [82,83], and geological problems [37,[84][85][86][87]. Specifically, the integration of FIB capabilities into a typical SEM allows for the removal of material with a high spatial control and precision to generate images of the freshly exposed material in situ within minutes.…”

High Spatial Resolution Evaluation of Residual Stresses in Shot Peened Specimens Containing Sharp and Blunt Notches by Micro-hole Drilling, Micro-slot Cutting and Micro-X-ray Diffraction Methods

“…volume we were able to enclose from shot peened sub-micron size grains regions down to the based material. A new version (1.6) of the FEI Slice and View TM software which incorporates a rocking polish (described in details in [58]) into an automated routine was used for the SST. A block of 100 × 66 × 30 μm 3 on the shot peneed surface of sample with 2 mm radius notch was sectioned.…”