XRF Advantages Non-destructive: No beam damage or coating of
sample Minimal Sample Preparation: conductivity not required sample
shape can be irregular Detection limits improve: 10x or better (vs.
SEM-EDS) Navigation by Optical Microscope Low Vacuum (~ 300 mTorr)
or No Vacuum (Air) More appropriate than SEM for larger scale
features X-rays are penetrating (microns to millimeters)
Slide 3
Sample Chamber / XYZ Stage Chamber Door Width ~ 500 mm Height ~
515 mm Can be set up to swing: Right to left (as shown) Left to
Right Open access to sample chamber
Slide 4
Manual Control and Analysis
Slide 5
Spectral Mapping: Mapping Examples
Slide 6
Elemental Spatial Distribution Maps: Paper Mg MapAl MapFe Map
Generation of BMP Elemental Maps Fe X-rays penetrate paper
Slide 7
Mapping Metal Analysis: Coins (Non-Destructive) * Rare Coin (2
Reichsmark - 1927?) * Pixels: 64 x 50 Map * Dwell time: 0.3 s/pixel
* Total time ~ 20 minutes Conclusion: Counterfeit Coin Conclusion:
Counterfeit Coin
Slide 8
Cl Mapping of Cement Core: Filtered Excitation Surface
Treatment Cross Section Cement Core Goal: To access diffusion of Cl
into cement from deicing agent where Cl could corrode supporting
steel Cores are cross-sectioned Rough cut (often there is a desire
to avoid polishing to minimize sample preparation or corruption of
the sample) Acquisition of data with Rh-tube, poly-capillary optic
and Al(thin) filter to remove interfering scatter from Rh(L) tube
line
Slide 9
Cement Chemistry Road Salt: Filtered Excitation Data courtesy
of J.M. Davis, Microanalysis Research Group NIST Map images
processed and displayed using Lispix SW Surface Treatment
Slide 10
Spectral Mapping - Bone Fossilization Fe Na K Si P Data
courtesy of George Havrilla, LANL
Slide 11
Map Tool: Substitution Map Image Overlay Fe Red K Blue Si
Yellow P Gray Na - Green Bone Fossilization
Slide 12
Map Tool: Elemental Image Overlay RGB Phase Analysis Bone
fossilization Ca Red Bone Si Green mineral P Blue Bone Substitution
Overlay Image: Ca-Si-P
Slide 13
Map Tool: Elemental Image Overlay RGB Phase Analysis Bone
fossilization Bone purple (Ca, P) New mineral orange (Ca, Si)
Slide 14
Spatial Distribution Maps: Facial Tissue Tissue masked with
carbon tape for Si-free zone Mapping region 15.6 mm x 11.3 mm
Slide 15
Map Tool: Data Mining Recall spectra from mapped pixels Hot Si
spots hide low-level Silicone coverage
Slide 16
Map Tool: 3-Log Band Image Scaling 3 individual color
logarithmic scales (NIST) Low level Silicone distribution exposed
in Green
Slide 17
Spectral Mapping with Poly-capillary and Filter Alumina
supported Catalysts Ag supported on Alumina SpheresPd supported on
Alumina pellets Objective: Measure metal distribution in ceramic
support Samples: Embedded in epoxy and cross-sectioned on one side
(no polish) Ag(L), Pd(L) versus Ag(K), Pd(K) L-lines probe ~ 20 m
into ceramic; no need to make a thin section K-lines probe ~ 4 mm
into ceramic; interference from opposite surface Map Acquisition:
Rh tube excitation requires filter to remove Rh(L) interference
Poly-capillary: ~ 55 mm FWHM lateral resolution at Ag(L), Pd(L)
Thin Al filter to remove Rh(L) from exciting spectrum True
Analytical flexibility in micro-XRF beam
Slide 18
Spectral Mapping Alumina supported Catalysts Ag(L) Map: Thermal
Image ScalingPd(L) Map: Thermal Image Scaling Objective: Measure
metal distribution in ceramic support Samples: Embedded in epoxy
and cross-sectioned on one side (no polish) Metal is concentrated
in the exterior shell of the ceramic support
Slide 19
Spectral Mapping Alumina supported Catalysts Ag(L) Map: 3 Log
Band Image ScalingPd(L) Map: 3 Log Band Image Scaling Objective:
Measure metal distribution in ceramic support Samples: Embedded in
epoxy and cross-sectioned on one side (no polish) Specialized Image
Scaling reveals important distributional details Ag(L) map shows
interior ring of Ag at weaker concentration, but no internal Ag
Pd(L) map shows the interior pellet has weak, uniform concentration
of Pd
Slide 20
High Resolution Spectral Mapping Odessa Meteorite (20mm x 16
mm) Area ~ 20 mm x 16 mm RGB Merge Fe Red Ni Green P - Blue
Elemental Image OverlayTotal Spectral Count Image (TSC Image) Fe
green Ni blue Cr cyan S magenta Cl yellow P - red
Slide 21
High Resolution Spectral Mapping Odessa Meteorite (20mm x 16
mm) Elemental Image Overlay P Cl Fe S Ni Fe
Slide 22
High Resolution Spectral Mapping Odessa Meteorite (20mm x 16
mm) RGB Merge Fe Red Ni Green P - Blue Fe:Ni (Kamacite) Fe:Ni
(Taenite) Fe:Ni:P( * ) (Schreibersite) * * * * * * * * * *
Slide 23
High Resolution Spectral Mapping Odessa Meteorite (20mm x 16
mm) RGB Merge Fe Red Ni Green S - Blue Fe:Ni (Kamacite) Fe:Ni
(Taenite) FeS (Troilite)