Item_Description_SOW.pdf

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ITEM DESCRIPTION #76MXSG-MXDTAA-20170126

for the purchase of a

Radio Frequency (rf) Glow Discharge Optical Emission Spectrometer

Jeffrey D. Childs, Ph.D.

Analytical Chemistry Section

76 MXSS/MXDTAA

1. SCOPE. This item description provides the salient characteristics for the procurement of a glow discharge optical emission spectrometer (GDOES) suitable for quantitatively depth profiling the elemental composition of metals, alloys, and aerospace coatings used on jet engines and aircraft.

2. BACKGROUND. The Analytical Chemistry Section, Oklahoma City Air Logistics Center (OC-ALC), Tinker Air Force Base, OK is responsible for the chemical analysis of metals, composites, aerospace coatings, and other materials used in the United States Air Force (USAF) aircraft and jet engines managed at OC-ALC. Alloy families frequently encountered include iron, aluminum, nickel, cobalt, titanium, copper, magnesium, lead, and zinc. A radio-frequency (rf) Glow Discharge Optical Emission Spectrometer (rf-GDOES) is needed for depth profiling both electrically conductive and electrically non-conductive aerospace materials as well as elemental quantification of bulk metal samples for bench stock quality control, failure analysis, and first article testing. Bulk analysis includes iron, aluminum, nickel, cobalt, copper, lead, magnesium, titanium, zinc, glass, ceramics, polymers, and plasma spray powders. Depth profiling applications include plating, galvanizing (Sn, Cr, Cd, Ni, Cu), thermochemical treatments(Carburizing, Nitriding, Carbonitriding), plasma spray coatings, YSZ thermal barrier coatings, clad (Aluminum), anodized coatings, oxide layers, paints, determination of contamination and cleanliness at surfaces and interfaces, determination of migration/diffusion at interfaces, determination of heterogeneity of coating/substrate, oxidation/corrosion, inclusions/blisters, and layer thickness.

3. SALIENT CHARACTERISTICS

3.1 DESIGN - The instrument shall be of the manufacturer’s current design. It shall be a new unit and include any additional features necessary to comply with the requirements specified herein. Additional features which are not specified herein, but are part of the manufacturer’s current design, shall be included in the furnished equipment.

3.2 SAFETY - The instrument shall be equipped with all necessary safety devices per National Electrical Code for protection against electrical shock hazard. It shall have any other protective devices as necessary to prevent injury to the operator, damage to the equipment, or erroneous data input or output.

3.3 WARRANTY – The complete spectrometer system, software, and interface boards will include an on-site 1 year warranty on all parts and labor to become effective on the day of installation acceptance by the government.

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3.4 GENERAL SPECIFICATIONS

3.4.1 Instrument shall be an optical emission spectrometer utilizing glow discharge argon plasma excitation suitable for chemical laboratory use.

3.4.2 Perform quantitative elemental depth profiling analysis of solid materials such as bars, rods, sheets, compacted plasma spray powders, jet engine turbine airfoils, jet engine components, aircraft skins, and aircraft components with depth resolution equal to or better than 1 nanometer. This will require that all channels are PMT channels (as opposed to CCD), due to the fast response time and higher sensitivity of PMT versus CCD.

3.4.3 Perform quantitative elemental depth profiling of surface and subsurface of aerospace coatings including plating, galvanizing (Sn, Cr, Cd, Ni, Cu), thermochemical treatments (Carburizing, Nitriding, Carbonitriding), plasma spray coatings, YSZ thermal barrier coatings, clad (Aluminum), anodized coatings, and oxide layers The depth resolution shall be 1 nanometer (nm) or better, and will therefore require PMT detection for ALL elements in Appendix 1. The depth profile will be valid from the first nanometer of surface down to 150 microns of depth with depth resolution of 1 nm at surface.

3.4.4 Instrument must have radio frequency (rf) excitation for quantitative depth profile analysis of both non-conductive samples and conductive samples. Instrument may also have Direct current excitation (in addition to rf) for analysis of conductive samples.

3.4.5 In addition to rf excitation, instrument must also be capable of Pulsed rf mode where duty cycle of the pulse (ratio of pulse width to pulse interval) is adjustable by the user.

3.4.6 Availability of special sample holders for analyzing small, non-flat, or odd shaped samples.

3.4.7 Analytical spot size (sputtered-crater-diameter) must be in two size ranges: 1) 1.5 mm-

2.5 mm and 2) 3.5-4.5 mm.

3.4.8 Polychromater will utilize a Paschen-Runge optical system with 1 meter focal length.

3.4.9 Spectral range of polychromater will be from 110 nm to 900 nm in first order.

3.4.10 Spectral resolution of polychromater equal to or better than 0.010 nm.

3.4.11 The polychromater must use photomultiplier tubes to simultaneously analyze all elements within ranges listed in Appendix 1 for the indicated bulk analysis programs and quantitative depth profiling methods.

3.4.12 Spectrometer shall be equipped with a Monochromater for full wavelength scanning to obtain, view, and analyze entire continuous spectrum. Monochromater will have focal length of

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1.0 m, spectral range of 160-500 nm, and resolution better than 0.010 nm. Monochromater will exhibit Czerny Turner geometry to provide ability for scanning entire wavelength region for qualitative and quantitative information as well as set at a particular wavelength for an element or wavelength not available on the polychromater so that all 58 channels in Appendix 1 can be analyzed simultaneously along with another selected channel chosen by monochromater position for a total of 59 channels.

3.4.13 For DC operation, the following six modes of operation can be accomplished with the user able to vary V, I, and Ar-pressure/flow rate: 1) voltage (V) constant with current (I) regulation meaning that I is adjusted to keep V constant, 2) V-constant with Ar-pressure-regulation, 3) V-constant with Ar-flow-rate-regulation, 4) I-constant with V-regulation, 5) I-constant with Ar-pressure-regulation, and 6) I-constant with Ar-flow-rate-regulation.

3.4.14 For rf operation, the following eight modes of operation can be accomplished with the user: 1) power-constant and pressure-regulated, 2) power-constant and voltage-regulated, 3) power-constant and Ar-flow-rate-regulated, 4) V-constant and Ar-pressure-regulated, 5)V-constant and I-regulated, 6) V-constant and Ar-flow-rate-regulated, 7) I-constant and Ar-pressure-regulated, and 8) I-constant and V-regulated.

3.4.15 Impedance matching shall be with either the Dressler-type rf-generator with L-C matchbox at 13.56 megahz or Hoffman-rf-generator-free-running-system that varies frequency (4 megahz-13.56 megahz) while keeping L-C constant.

3.4.16 Source shall be either Grimm geometry with rf powering to the cathode block, which by contact transmits the rf potential to the surface of the sample cathode or Marcus-type source with potential applied directly to back side of sample rather than to the front through contact with the cathode block. Source shall be of a dual-vacuum pump design, according to which the bulk of the discharge volume and cathode dark space region are evacuated separately.

3.4.17 Stainless steel tubing in the vacuum system.

3.4.18 The vacuum pump for the plasma source shall be oil free.

3.4.19 Include an Argon gas purifier with a flow rate up to 10 L per minute.

3.4.20 Include a device for direct sample water cooling.

3.4.21 Instrument must be able to depth profile the following types of samples encountered in Air Force depot activities with a depth resolution of better than or equal to 1 nm where depth profile is valid from the first nanometer of surface down to 150 microns.

1) Phosphoric Acid Anodized (PAA) and primed 2024-Al skin I.A.W. Boeing Specifications where P, O, Cr, C, N, S are depth profiled.

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2) AMS 2481 anti-chafing phosphate treatment to show elevated oxygen and phosphorous I.A.W. AMS 2481.

3) Nitriding treatments of roller and inner race of bearing components (M50-tool steel-substrate) to depth profile [nitrogen] as high as 8% on surface and as a function of depth to be correlated on occasion with XRD-determined residual stress as function of depth.

4) AMS 2485 black oxide anti-chafing treatment of low alloy steel to depth profile oxygen at surface.

5) NiCrAlY bond coats air plasma sprayed onto Rene N6 and other Ni-based superalloy engine components.

5) Carburizing and nitro-carburizing of bearings and correlate with residual stress as function of depth. Carbon, Nitrogen, and base metal alloying elemental concentrations as function of depth.

6) Diffusion aluminide coatings on Ni-based superalloy turbine blades and engine components where Aluminum, major alloying elements of superalloy, and sulfur are all depth profiled in turbine blades.

7) 7075-Al that is clad with nominal 30 microns of 7072 as well as all other aluminum-clad combinations to determine chemistry and depth of clad.

8) Yttria stabilized zirconia (YSZ) ceramic top coats of thermal barrier coatings that have been air plasma sprayed onto engine components to depth profile top coat, bond coat, and thermally grown oxide layer.

9) Cu-Ni-Indium air plasma spray coatings on parts and coupons to determine chemistry as function of depth.

10) Nickel plating, Cr plating, Ag-plating and Cu-strike, and electroless-Ni plating on iron based substrates to determine chemistry and impurity level as function of depth.

11) Ni-Al air plasma spray coatings on Ni-based substrates to determine chemistry and depth of coating.

12) Tungsten-carbide cobalt air plasma spray coatings on titanium substrates to determine chemistry as function of depth.

3.4.22 Software shall perform the minimum following functions:

a) Ability to create quantitative depth profiling (QDP) applications and bulk analysis applications shown in Appendix 1.

b) Optimization of bulk analysis excitation parameters for various matrices.

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c) Quantitative chemical analysis of bulk samples.

d) Concentration in mass percent versus depth for quantitative depth profiling (QDP) applications.

e) Sputtering rate versus depth for QDP methods.

f) Density versus depth for QDP methods.

g) Ability to export data to other programs such as Microsoft Excel.

h) For RF-excitation, peak to peak voltage, bias voltage, and pressure are measured as function of time/depth. For DC-excitation, voltage, pressure, and current are measured as function of time/depth.

3.4.23 The instrument shall be delivered with any consumables required for the initial operation of the instrument and a sufficient supply to allow 3 months of operation.

3.4.24 The instrument will include QDP method with the 58 channels/elements listed in Appendix 1. The instrument will also include 8 bulk programs with given base metals: Fe, Ni, Ti, Cu, Zn, Al, Mg, and Co.

3.4.25 The calibration mode for the QDP method(s) will be a sputtering rate correction mode whereby concentrations of standards in the calibration curves are calculated from intensities according to the sputtering properties of the standards comprising calibration curves. The sputter rates of these calibration standards must be known. The sputter rate of the unknown samples will be determined from the multi-matrix QDP calibration curve.

3.4.26 The calibration mode for the bulk methods will use intensities of the analytical channels divided by intensity of reference channel on the x-axis, and the percentage values of the calibration samples divided by the concentration of the element corresponding to reference channel.

3.4.27 QDP algorithm for calculating concentration from measured intensities will have option to either use or not use Argon (415.2 nm) as internal standard to suppress noise and voltage dependencies. Calculation steps include 1) Plasma corrections that will include balancing of current fluctuations for DC operation and balancing of power fluctuations for rf operations. 2) balancing voltage fluctuations (in the case of RF excitation, voltage is iteratively approximated from plasma-corrected and matrix-corrected Ar-intensity. 3) matrix correction and line interference correction. 4) normalizing primary concentrations of 100%. 5) Calculating the sputtering rate using normalization factor.

3.4.28 The instrument shall be configured to quantitatively depth profile all elements shown in the table of Appendix 1 using rf excitation and/or DC excitation. The instrument shall be able to quantify elements in both QDP applications and bulk analysis application in the ranges specified in Appendix 1.

3.4.29 The voltage on each PMT must be able to be adjusted by user at any time to a low voltage (500 V), high voltage (950 V), or mid voltage (725 V) so as to maximize signal to noise

6/9 al low signals and avoiding saturation at high signals.. Alternatively, the computer will vary the voltage on each PMT inversely to the signal in order to avoid saturation at high signals and maximize signal to noise ratio at low signals.

3.4.30 Primary slit scanning so that intensities of all channels are plotted against position of primary slit and primary slit position can be adjusted to optimal profiling position.

3.5 ON-SITE INSTRUMENT VERIFICATION AND TRAINING

3.5.1 The vendor shall provide on-site verification by demonstration that the instrument is in working order and meets the salient characteristics of this item description.

4.1 QUALITY CONFORMANCE INSPECTION

4.1.1 The instrument shall meet the salient characteristics of this item description, conform to the vendor’s own drawings, specifications, standards, and quality assurance practices.

4.1.2. Demonstrate in the presence of a government representative that the instrument can accurately quantify the elemental compositions corresponding to ranges in Appendix 1 as well as demonstrate that depth resolution is 1 nm for applications listed in 3.4.21.

4.1.3. Certified reference materials to be analyzed using RF-QDP method include Nickel based superalloys: MBH 219x1867, IMZ-181, 24XWASP3; Co-Mo alloy: MBH112X-14937-M and NIST 1199; Iron: Brammer standard BS59C and NIST 1152a; Aluminum: NIST 1256 and ARMI ALC-7075-AD; Titanium: NIST 654b and ARMI IARM 177b; Copper: Brammer Standard BS630 and Brammer Standard BS857.

4.1.4 In house standards to be analyzed and compared to previous rf-QDP data include four phosphoric acid anodized and primed 2024-Al panels that are electrically nonconductive.

Appendix 1. Instrument must contain sufficient number of photomultipliers (PMT channels) so that all elements in below table (continued on next page) are quantified simultaneously for any concentration in the listed ranges during radio frequency (RF) quantitative depth profiling application. The voltage on each PMT tube will be determined by the actual elemental concentration within listed range, and will be adjustable either prior to experiment by user or dynamically during experiment by computer to avoid saturation at high signals and maximize signal to noise ratio at low signals.

Depth profiling

Bulk analysis Matrix modules

Element WAVELENGT H (nm)

Fe Al Ni Co Ti Cu Mg Zn

Ag 338.289 X (0-100) 0.005 -

0.2

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Al 396.152 X (0-100) 0.003-2 matrix 0.001 -

0.001 -

0.005 –

0.02 - 11 0.001 - 60

As 189.042 X 0.08-0.2

Au 211.068 X (0-100) 0.001 -

0.05

B 208.959 X 0.0005-

0.1

0.002 -

0.03

0.001 -

0.02

0.001 -

0.02

Be 313.042 X 0.003 -

0.06

Bi 306.771 X 0.002 -

0.005 -

1.2

C 153.143 X (0-100) 0.001-

5.0

0.003 -

0.2

0.005 -

0.01 -

0.1

0.003 -

0.03

Ca 393.367 X 0.0003 -

0.001 -

0.03

0.002 - 0.02

Cd 228.802 X (0-100) 0.005 -

0.7

Ce 413.765 X 0.005-

0.01 - 2

Co 345.351 X(0-100) 0.003 -

0.005 -

1.5

0.001 -matrix

Cr 425.433 X(0-100) 0.001-4 0.001 -

0.3

0.005 -

0.005-4 0.001 -

0.001 - 0.05

Cr2 267.716 1.0-40 1 - 30 15 - 35

Cu 327.396 X(0-100) 0.001 -

0.002 -

0.002 -

2.0

0.005 -

0.1

0.002 -

0.5

MATRIX 0.01 - 0.13 0.001 – 3

Cu2 219.226 4-12 20 - 35

Fe 371.994 X (0-100) 0.005 -

1.5

0.003 -

0.01-5 0.005 -

2.5

0.01 - 0.04 0.002 - 0.1

Fe2 238.204 matrix 5 - 35 5- 50

H 121.567 X(0-100)

Hf 286.637 X 0.1 - 1.4

In X(0-100)

K X

La 433.734 X 0.001-

0.025

0.01 - 1.2

Li X 0.002- 0.025

Mg 383.829 X(0-100) 0.001- 0.4

0.005 -

0.005 -matrix 0.005 - 0.1

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Mn 403.449 X 0.005-

0.003 -

1.5

0.01 - 2 0.005 -

0.005 -

0.004 - 0.5 0.001 - 0.05

Mo 386.411 X(0-100) 0.001 -

0.005 -

0.005 -

0.002 -

N 174.272 X 0.02-1

Na X 0.001 -

0.03

Nb 316.340 X 0.003 -

0.3

0.005 -

5.0

0.005 -

0.01 - 7

Nd 430.357 X

Ni 341.477 X(0-100) 0.001-4 0.001 -

3.0 matrix 0.01 - 2 0.002 -

0.8

0.002 - 0.01 0.001 - 0.05

Ni2 225.386 2-40 2 - 35 2.0 - 30

O 130.217 X(0-100)

P 178.287 X 0.002-

1.0

0.001 -

0.04

0.003 -

0.04

0.001 -

0.0005 - 0.3

Pb 220.353 X 0.002 - 0.6

0.5

0.005 -

0.03

0.002-

0.001 - 1

Pd 340.458 X

Pr

Pt X

Re 346.046 X 0.01 -

2.9

S 180.731 X 0.001-

0.001 -

0.04

0.002 -

0.05

Sb 206.833 X 0.002-

0.001 -

4.1

0.005 - 0.2

Se X 0.005 -

1.65

Si 288.157 X 0.001-

5.0

0.001 -

0.002 –

0.01 -

1.5

0.001 -

0.2

0.001 -

0.01 - 0.2 0.001 - 0.1

Sn 303.412 X 0.002-

0.2

0.003 -

6.5

0.01 - 3 0.003 -

0.004 - 0.04 0.005 - 0.1

Sr 407.771 X 0.002 -

0.15

Ta 362.662 X 0.001-

0.005 -

6.5

0.005 -

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Te X 0.002-

0.08

0.002 -

0.06

Th 401.914 X

Ti 334.941 X(0-100) 0.001 -

0.002 -

0.3

0.003 -

5.0

0.005 -matrix

Tl X

V 411.179 X 0.002 -

0.05

0.003 -

0.005 -

0.005-

W 429.461 X(0-100) 0.005 -

0.01 -

0.01 -

Y 371.029 X 0.001-

Zn 330.294 X(0-100) 0.002-

0.001 -

1.0

0.005 -

0.01 - 7 matrix

Zr 360.119 X(0-100) 0.001-

0.2

0.003 -

0.2

0.003 -

0.1

0.005 -

Ar 415.2