s28_non-destructive elemental and microstructural analysis of construction materials_ltc2013

7/29/2019 S28_Non-Destructive Elemental and Microstructural Analysis of Construction Materials_LTC2013

1/47

2013 Louisiana Transportation Conference

Session 28: Materials and

Testing- Application of

XRF, XRD


2/47

Topic

the application of non-destructive elemental

and micro-structural analysis of construction

Materials such as cement, fly ash, metals,

glass, and paint pigments etc. utilizing X-RayFluorescence and X-ray Diffraction technology

Moderator: Richie Charoenpap Presenter: Stephen Williams


3/47

Materials Testing

Archimedes and the golden crown

http://www.math.nyu.edu/~crorres/Archimedes/Crown/CrownIntro.html


4/47

X-Ray Analysis

XRF: X-Ray Fluorescence

XRD: X-Ray Diffraction

Quantitative and qualitative

analysis of elements (XRF)

and compounds (XRD)

Wilhelm Conrad RntgenDiscovered X-Rays

8 November 1895

Nobel Prize 1901http://en.wikipedia.org/wiki/Wilhelm_R%C3%B6ntgen


5/47

X-rays are part of the electromagnetic spectrum

A rainbow of colors

X-Rays


6/47

X-Ray Lines

Characteristic radiation

Siegbahn Notation


7/47

The Nobel Prize in Physics 1915

William Henry Bragg

Wavelength is a function of d spacing and diffraction angle

Bragg's Law was derived by physicist Sir William Lawrence Bragg in 1912

http://en.wikipedia.org/wiki/Bragg%27s_law

William Lawrence Bragg

n = 2d sin


8/47

Diffraction and Braggs Law

= d sin + d sin = 2d sin(Braggs law)

dsin dsin

d

A C

B

B'

B"

C'

C"

A'

A"

d

x

C DB

x


9/47

Characteristic X-Ray Lines

Elements produce lines

with discrete energies

depending on the

atomic number of theelement

Moseleys Law (1913)

http://en.wikipedia.org/wiki/Moseley%27s_law

)( 21 KerAtomicNumbKFrequency

K1 & K2 are constants


10/47

XRF

Quantitative Elemental Analysis


11/47

Alternative Technologies: Elemental Analysis

AASGFAAS

ICP-AES

ICP-MS

1 ppq 1 ppt 1 ppb 1 ppm 1,000 ppm 100%

Arc-Spark OES

Total OC, TN, TS, TOX

BULK

XRF

Liquids

Solids

Chemical Methods

TRACE


12/47

Periodic Table of the Elements: XRF


13/47

Examples of XRF Samples

Fused Beads

Pressed Powders Metals

Liquids


14/47

XRF techniques

Energy Dispersion

Uses a detector that can

distinguish different

energies

Wavelength Dispersion

Uses single crystals or

multi-layer to diffract

selected wavelength intothe detection system

Theory of XRF, Peter Brouwer ISBN: 90-9016758-7 3rd Edition


15/47

Fundamental Parameters

Can calculate the relative XRF intensities for elemental components

Given measured intensities, concentrations can be estimated usingiterative calculations

Detector performance still needs to be calibrated using real materials


16/47

XRF Calibration: S and Fe in Water

Calibration

using raw

intensity data

Calibration using

matrix corrections


17/47

17

Optical Emission: Calibration

OBLF VeOS OES


18/47

Applications for XRF

Steel Making

Cement Manufacturing


19/47

Sample Preparation: Issues

Physical form of the

material affects the

analysis results

Matrix correction onlyaccounts for absorption

and enhancement Fused Beads

R2

= 0.9996

0

100

200

0 50 100

Conc SiO2 (wt %)

Corr.countr

ate

(kcps)

Pressed Powders

R2

= 0.9642

0

100

200

0 50 100

Conc SiO2 (wt %)

C

orr.countrate

(kcps)


20/47

Universal vs. In Type Calibrations

Pressed powder, production control calibrationsFused Bead Refe rence cali brati on

0

100

200

0 50 100

SiO2 (wt %)

Countrate

(kcps)

Fused Bead Calibration Pressed Powder Calibrations


21/47

Some Sample Preparation Equipment

Herzog PressHerzog Milling Machine PANalytical Fusion Machine

Rocklabs shatterbox

and grinding bowl

Buehler

Polishing disk


22/47

Phosphorous Content in Asphalt

Terry Arnold

Federal Highway Administration

Turner Fairbank Highway Research Center

McLean VA


23/47

PANalytical XRF systems

Epsilon 3 Energy

dispersive spectrometer

Axios Wavelength

dispersive spectrometer


24/47

XRD

Qualitative phase identification

Quantitative phase analysis


25/47

X-Ray Diffraction of Crystaline materials

= d sin + d sin = 2d sin(Braggs law)

dsin d

sin

d

A C

B

B'

B"

C'

C"

A'

A"

d

x

C DB

x


26/47

Atoms, Crystals and Crystallites

Particles may consist of many crystallites

http://en.wikipedia.org/wiki/Rutile

http://en.wikipedia.org/wiki/Aragonite


27/47

Norelco XRD Serial #2 Circa1942


28/47


29/47

Qualitative Phase Analysis

The diffraction pattern is a

fingerprint of the crystal

structure

Large numbers of materials

have been documented

ICDD


30/47

Uses of X-ray Diffraction

Most popular use of X-Ray Powder Diffraction

is Qualitative Phase Identification

Quantitative applications have always existed.


31/47

XRD Samples


32/47

Basic Optics using the XCeleratorDetector


33/47

Diffraction pattern of Quartz

20 30 40 50 60 70 80

2Theta ()

0

10000

40000

90000

160000

Intensity

(counts)

Angular Position

Relative intensities


34/47

Pigment TiO2: Anatase and Rutile

Rutile Anatase

Chemistry TiO2 TiO2

Color Brilliant white Pale yellow white

Hardness 6.5 5.5

Density 4.2 3.9

Crystal type Tetragonal, space group

136

Tetragonal, space group

I41/amd

I/Ic 3.54 5.04

Common uses Pigments, refractory

ceramic, sunscreen,

cosmetics, etc

photcatalyst

Unit cell structure


35/47

XRD of TiO2

Bottom scan Titanium

metal, middle scan Anatase,

above 550 C converts to

more stable Rutile form (top

scan)

Easy to quantify RIR method works

perfect, no standards, no calibration,

no monitors, just measure height or

area of most intense peak for each to

calculate.
http://www.google.com/url?sa=i&rct=j&q=&esrc=s&frm=1&source=images&cd=&cad=rja&docid=AeEPlo0Fix4JbM&tbnid=fm1rSK2lvWIE4M:&ved=0CAUQjRw&url=http://www.scielo.br/scielo.php?pid=S0103-50532008000600002&script=sci_arttext&ei=bmoZUabTCYnOyAGttIGgDw&bvm=bv.42080656,d.eWU&psig=AFQjCNHmdS4hnf5QprmkOBUTH7h2RIRJJQ&ust=1360706387571960


36/47

Phase Composition of Cement

Robert Herman Bogue: Calculation of

compounds in Portland cement, 1929

Estimate the compounds from the elemental

analysisAlite: C3S, or tricalcium silicate

Belite: C2S, or dicalcium silicate

Aluminate phase: C3A, or tricalcium aluminate

Ferrite phase: C4AF, or tetracalcium aluminoferrite

http://www.understanding-cement.com/bogue.html


37/47

Hugo Rietveld

The Rietveld method uses all

XRD peaks and the complete

profile for the analysis:

Rietveld is the only practical

method to directly quantify

phases in clinker/cement

http://en.wikipedia.org/wiki/Hugo_Rietveld


38/47

38

2Theta

20

2Theta

30

2Theta

40

2Theta

50

Counts

1) C3A

2) C4AF

3) C3S

4) C2S

0

500

1000

1500

2000

0

100

-100

Quantitative Rietveld Analysis of Clinker

(4 main phases only)


39/47

Free Lime in Cement

2000

4000

6000

Counts

Position [2Theta]

36.50 37 37.50 38

C2S

CaO

10.0% CaO

0.25% CaO

C2S

Free LimeMeasurement


40/47

Residual Stress

Unstressed sample

Stressed sample

y

d

y

d

d

sin2y

d

sin2y

http://en.wikipedia.org/wiki/Residual_stress


41/47

Residual Stress determined by XRD

Lab XRD system

Monocapillary optic

X-ray Lens

Bearings, Car Wheels, structural elements


42/47

Sample Preparation in XRD

Preferred Orientation

Extreme problem for samples with crystal-

related shape or non-spherical particles

Preferred orientation Random orientation


43/47

Mica Thin Layer Sample: Dusted vs. Pressed

dusted

pressedhk0


44/47

Sample Preparation for Powdered Materials

Packed Powders Low Background holders Capillaries

Solid Samples


45/47

PANalytical XRD systems

Empyrean XRD XPert Powder XRD


46/47

The End

Thank You


47/47

Powder Diffraction: Poly-Crystalline Sample

= 2 d sin()

s28_non-destructive elemental and microstructural analysis of construction materials_ltc2013

Documents