EMPOWERING RESULTS

GDS850AGlow Discharge Spectrometer

GDS advantages over other analytical techniques

� Linear calibration curves with wide dynamic range

� Low Argon gas consumption

� Separation of sputtering and excitation

� Less self absorption and no material re-deposition

� Atomic emission consists primarily of ground stateatom lines, resulting in fewer lines and reducedinterferences

� Freedom from metallurgical and chemical history

� Fewer standards required for calibration

� Minimal memory effects for a quickmatrix change

� Automatic cleaningbetween samples

GDS850A Glow Discharge Spectrometer

Delivering customers a true turn-key solution, the GDS850A is configured and calibrated at the factory, inorder to provide a custom analytical tool optimized to your sample matrices. Due to the robust nature of thesystem, samples can be analyzed immediately after installation. Only LECO provides this level ofcustomization and customer support.

Using the latest technology in hardware and software, the GDS850A is designed to enhance the performanceof both process control and R&D applications. This instrument covers a wide spectral range (120 to 800 nm)and allows for custom configurations of up to 58 channels. Compared with spark sources, GD-AES employs anon-thermal glow discharge source for atomic excitation. Excitation of the atoms occurs in the glow dischargeplasma discretely apart from the sample surface thereby reducing the metallurgical and chemical historyinherent in all samples. Emission of ion wavelength spectra is almost completely eliminated thereby giving riseto less complex spectra typical of thermal excitation sources.

This unique method of excitation results in true bulk analysis providing a distinct advantage in accuratelyidentifying chemical compositions, especially of difficult materials, over other excitation methods.

LECO Glow Discharge Atomic Emission Spectrometers (GD-AES) are the clear choice of leading companiesaround the world, providing the most accurate bulk analysis, as well as quantitative depth profiling for a widevariety of sample matrices and applications.

The Power of Glow Discharge SpectrometryThe signature "sputter spot" fromglow discharge spectrometry showsuniform sample removal and providesthe large representative area neededfor accurate sampling of bulk contentand depth profile information.Competitive methods cannot providethis quality of data because of theirrandom sampling processes. Thecathodic sputtering process of theGrimm-type lamp is created byapplying a controlled voltage,current, and argon pressure to thesample surface. The diagram belowdetails the excitation and emission ofthe sample atoms in the argonplasma. Reduced line interferences byglow discharge result in simple linearcalibrations. GDS delivers higherprecision with fewer calibrationstandards for an unbeatableadvantage over arc spark.

Other methods may preferentially attack the samplesurface and do not always provide a representativesample to analyze. With glow discharge spectrometry,sample material is uniformly sputtered from the surface.The non-thermal nature of the sampling process makesthis an excellent technique for difficult applications. Thesputtering produces atoms for excitation that takes placeaway from the sample surface.

When the excited atoms return to ground state, theyemit light. Each wavelength emitted is characteristic ofthe element from which it came. A holographicdiffraction grating separates and focuses the light bywavelength. Exit slits pass the light of your chosenelements on to the detectors for accurate measurement.

Bulk Performance PlusUnlike other methods, GDS can handle your bulk applications like sheet,powder, fastener, pressed, and mounted samples. Even small samples likewire (0.25 mm diameter) can be accurately tested. Thin sheets (down to 0.02mm in thickness and even thinner) may be successfully analyzed using abackplate and cooling puck. Just about any sample form can be characterizedby glow discharge technology. The flexibility of LECO instruments allows youto easily add depth profiling capabilities as your needs change.

The LECO GDS source offerscomplete flexibility for controlof operating parametersincluding current, voltage,and pressure.

Bulk ApplicationsLECO delivers a fully calibrated instrument based on your applications.

• Iron (as-cast, chilled-cast,gray, ductile)

• Brass/Bronze (leaded)• Nickel• Cobalt• Titanium• Tungsten• Magnesium

• Aluminum (high Si, composites)

• Steel (low and high alloyed,leaded, resulfurized)

• Copper• Low Melting Point Alloys• Powdered Metals

• Solders (Zn, Pb)

• Carbides

• Elements not in Solid Solution

• Zinc

Ni calibration in stainlesssteel. Calibration curveexhibits linearity and widedynamic range.

Use the Windows -based toolbars and drop-downmenus to select a variety of analytical procedures.Simply select a method, choose the samples andstandards to be analyzed, and start.

®

The software allows sampling rates of up to 2000data points-per-second regardless of the number ofchannels selected. Results from ppm levels can beviewed on a large color monitor.

Multiple sample presentation of bulk data using theGDS850A Glow Discharge spectrometer displayingall samples analyzed in a simple organizedspreadsheet.

Calibration Screen

Single sample screen of a certified checkstandard can be easily monitored for

elements of interest and accuracy.

Accurate Bulk AnalysisIdeal for foundries, die casters, smelters, and all ferrous/nonferrous applications.

Quantitative Depth Profiling (QDP) SolutionsQDP is an ideal method for early identification of potential problems with your materials (including coatings, layers, andthermochemical treatments). Why use GDS? The GDS technique can perform a depth profile analysis continuously fromnanometers to hundreds of micrometers. Combined with a fast sputtering rate (0.5 µm to 30 µm/min.), GDS provides thecomplete chemical composition (ppm to 100%) from the surface to the substrate in only a few minutes. All elements are acquiredsimultaneously, increasing sample throughput while minimizing cost-per-analysis.

LECO offers you the ultimate Glow Discharge Spectrometer capable of quantifying thin alternating multi-layers.

QDP ApplicationsYour instrument will be fully calibrated for your specific application upon delivery.

• Glass/Ceramics

• Galvanizing (EG, Hot Dip, Galvalume, Galvanneal, Galfan, Zinc-Nickel)

• Thermochemical treatments (Carburizing, Nitriding, Carbonitriding)

• Oxide layers

• Semiconductors• Organic coatings• Plating (Sn, Cr, Cd, Ni, Cu)

• Hard coatings made by PVD/CVD• Clad (Aluminum)

• Contamination and cleanliness at the surface and interfaces• Inclusion/blister• Chemical composition

• Migration and diffusion at interfaces• Heterogeneity of coating/substrate

• Oxidation/corrosion

• Layer thickness/coating weight• Adherence issues

QDP Quickly Identifies

Thin Alternating Multi-Layers

Example of stable in less than 5 ms.fast startup plasma

Zoom showing the composition of the PVD coatinglayers of boron carbide and titanium on silicon,providing resolution in the nanometer range.

Depth (micrometers)

An

aly

tew

eig

htp

erc

en

t

0 0.5 1 1.5 2 2.5 3 3.50

10

20

30

40

50

60

70

80

90

100

B ×3C ×10OSiTi

B

Si

C

Si

O

Si

B

O

Ti

B

O

Ti

Depth (micrometers)

An

aly

tew

eig

htp

erc

en

t

0.7 0.71 0.72 0.73 0.74 0.75 0.7645

50

55

60

65

70

75

80

B ×3C ×10OSiTi

B

C

Ti

B

C

Ti

B

C

Ti

B

C

Ti

Time (sec)

Analy

tein

tensi

ty(v

olts)

0 0.01 0.02 0.03 0.04 0.05

0

100

200

300

400

500

600

700

800

*TP ×10

*I (mA) ×10

*V (volts)

*TP

*I

*V

*TP

*I

*V

*TP

*I

*V

*TP

*I

*V

*TP

*I

*V

Quantitative Depth Profiling (QDP) Solutions

Three replicate QDPs of the surface of ahard disk exhibiting seven resolved layersat a depth of 100 nanometers.

QDP analysis of organic coatings. QDP ofpainted steel sheet showing three different

organic layers—topcoat paint andprimer—on the galvanization (Zn).

Depth (micrometers)

An

aly

tew

eig

htp

erc

en

t

0 10 20 30 40 500

10

20

30

40

50

60

70

80

90

100

FeCCr ×2ON ×5P ×50Si ×5Ti ×10ZnH ×2

Fe

C

Fe

Cr2

Fe

O

Zn

N

Zn

Cr

P

Si

Ti

ZnFe

C

O

Si

H

C

N

P

Ti

H

QDP of the corrosion-resistant electro-galvanized Zn/Ni coating on the surface ofsheet steel, showing coating thickness, weight,and alloy composition.

Depth (nanometers)

Analy

teato

mic

perc

ent

0 20 40 60 80 100 120 140 160 180

0

10

20

30

40

50

60

Al

Al

B

B

C

Co

Co

Cr

Cr Cr

Hf

O

Pt

Ru

Ru

Ta

Ti

Ti

S ×10

Si

S

O

Al

QDP analysis of multilayer sample, includingconductive and non-conductive layers. Example

of TiN, TiCN, Al O , TiN, and TiCN on cementedcarbide. Display of Atomic % vs. Depth for

stoichiometry check.

2 3

Depth (micrometers)

Analy

teato

mic

perc

ent

0 5 10 15 20 25 30 35

0

10

20

30

40

50

60

70

Al

O

C

Co

Ti

W

N

Al

C

Co

O

Co

W

Al

C

Ti

W

N

O

C

Ti

N

Al

O

C

Co

Ti

O

Ti

W

N

Meeting production, process, and research requirements.

Depth (micrometers)

An

aly

tew

eig

htp

erc

en

t

0 1 2 3 4 5 6 70

10

20

30

40

50

60

70

80

90

100

FeZnNi

Fe

Zn

Fe

Ni

Fe

Zn

Fe

NiFe

Zn

Ni

Zn

Ni

Name Zn Depth, µm Coating Wt, g/m² Zn% Ni%Zn-Ni 1 2.72 19.93 87.36 12.61

LECO Corporation3000 Lakeview Avenue | St. Joseph, 49085 | 800-292-6141 | Phone: 269-985-5496MI

info@leco.com | www.leco.com | -9001:2015 Q-994 | LECO is a registered trademark of LECO Corporation.ISO

EMPOWERING RESULTS

Form No. 209-056 6 © 2019 CorporationLECO12/19-REV

Aluminum Calibration CurvePower Pressure Control Mode

R2

= 0.9733

0

20

40

60

80

100

120

140

160

180

200

0 0.5 1 1.5 2 2.5 3

Intensity

Al

Standards

Cu/Al

Standards

Zn Standard

Pure Fe

and Cu

Standards

Calculated

Curve

Con

cen

tra

tion

x S

R

Aluminum Calibration CurveVoltage Curve Control Mode

R2

= 0.9992

0

20

40

60

80

100

120

140

160

180

200

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

Intensity

AlStandards

Cu/AlStandards

Zn Standard

Pure Fe and CuStandards

CalculatedCurve

Con

cen

tra

tion

x S

R

In conjunction with LECO's patented front coupling is the exclusive treatment of RF power to ensure that lamp parameters areconstant regardless of matrix and material thickness. TPP is power control in real-time which compensates for the variousRF power losses. Compensated losses include transmission losses, absorption losses, and radiative losses, in addition to real-time compensation of reflected power.

It has been well documented that GD lamp conditions are affected by specimen matrix. It is necessary to apply precise controlto the voltage and current for accurate quantification. The voltage-current relationship is important for accurate and consistentresults and these parameters can be measured directly in DC. In contrast, for RF, only the voltage and power in Watts can bemeasured. When the TPP is held constant and the voltage is maintained precisely by varying the lamp pressure, the currentis also constant. In this manner the DC control mode is emulated where both voltage and current can be measured and areheld constant.

True Plasma Power (TPP)®

RF Source OptionWith an additional RF option, the GDS is capable of quantifying non-conductive thin oxide layers, at nanometer resolution, onmaterials such as stainless steel.

Traditional Control Mode LECO Control Mode

45

40

35

30

25

20

15

10

5

00 0.005 0.01 0.015 0.02 0.025 0.03 0.035

C

C

O

O

Fe x 0.5

Ca x 50Mn x 5

Cr

Cr

Cr

Si

Si

Depth (Micrometers)

We

igh

t %

Fe

Ca

Mn

QDP of a stainless steel coupon coated with a 5 nm oxide layer.