1. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 1 Electroformed Nanocrystalline Coatings An Advanced Alternative to Hard-Chrome Electroplating PP-1152 Dr. Maureen J. Psaila-Dombrowski, McDermott Technology, Inc. Douglas E. Lee, Babcock & Wilcox Canada Dr. Jonathan L. McCrea, Integran Technologies Dr. Uwe Erb, University of Toronto HCAT Meeting, Toronto, Ontario August 30, 2001

2. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 2 Contents  Technical Objective  Nanocrystalline Materials  SERDP Program Overview  Phase I Results  Phase II Optimization  Phase II Next Step

3. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 3 Technical Objective  Develop an environmentally benign advanced nanocrystalline Co-based coating technology that:  Is compatible with conventional electroplating infrastructure  Will produce coatings that meet or exceed the overall performance of hard chrome (hardness, wear, fatigue, corrosion, and thermal stability)  Has costs similar to or less than life-cycle cost of existing hard chrome electroplating processes  Will be applied to non-line-of-sight surfaces

4. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 4 Nanocrystalline Materials Introduction  Introduced 20 years ago  Enhanced volume fraction of the boundary component  Superior mechanical properties  Produced by a variety of techniques:  Physical and chemical vapor phase processing  Mechanical attrition  Crystallization of amorphous precursors  Electrochemical methods

5. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 5 Nanocrystalline Materials Synthesis  Electrodeposited via conventional electroplating techniques  Single step process  Fully dense material - chemically homogeneous  Pure metals, binary/ternary alloys, composite materials  Broach choice of alloying constituents and bath chemistry  Pulsed power supply to favour nucleation of grains instead of grain growth  Fixed or consumable anodes  Plated or freestanding material with a broad range of thickness (1  to 1mm)

6. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 6 Nanocrystalline Materials Structure & Solid, fully dense electrodeposits (virtually zero porosity) & Grains and well characterized grain boundaries (similar to conventional polycrystalline materials) & 3 to 100nm grain size

7. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 7

8. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 8 † ASM Metals Handbook, ASM International, Metals Park, OH. Vol. 2, p. 437 (1993) Mechanical Properties of Conventional and Nanocrystalline Nickel

9. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 9 Program Three Phases  Phase ITechnology Viability Assessment  completed  Phase IICoating Optimization  in process  Phase IIIExtension to Complex Shapes  next year

10. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 10 Phase I Results  Go/No Go Nanocrystalline Material Data Alloy I Alloy II Alloy III Co-P Co-Mo Co-Fe-P (0 to 5wt%P) (0 to 1wt%Mo) (15-30%Fe,2.5%P) 1) Grain size (nm) 8-14 8-14 15-25 2) Microhardness (VHN) 575-820* ~575 520-900** 3) Thermal Stability (  C) 485 up to 497 425 4) Coating Thickness/≤ 0.010” ≤ 0.002” ≤ 0.05” IntegrityNo N/A No Pits/Pores *Hardness increases up to 1100 when heat treated 5 minutes @ 450  C **Hardness increases up to 1250 when heat treated 10 minutes @ 400°C

11. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 11 Phase II  Select most promising alloy (Co-Fe-P) and optimize composition, grain size and deposition process  cleaning and activation procedures  plating procedure  heat treatment procedure  grinding/polishing procedure  Apply to high strength and low strength carbon steel substrates (.003 to.010” thickness)

12. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 12 Phase II  Define formal testing requirements and conduct tests. Include pertinent requirements from existing HCAT protocols and program data. Meet or exceed hard chrome performance requirements.  Mechanical testing  hardness  tensile strength  ductility  adhesion  coefficient of friction  Performance testing  fatigue  corrosion  embrittlement  wear  Go / No-go decision  Reports and Review

13. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 13 Phase III  Extension to Complex Shapes  Adapt processes and develop equipment for DoD non-line- of-sight applications  Suitable anodes  Fluid delivery system  Optimized rate of deposition and coating quality  Apply optimized alloy composition developed in Phase I and II to an actual DoD part/s for DoD evaluation  Identify coating inspection technique

14. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 14 Program Plan

15. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 15 Phase II Optimization  Co-Fe alloy  Variation of electrical parameters (I avg, pulse time, frequency)  Cobalt chloride-ferrous sulphate bath chemistry  Results  Electrodeposits demonstrated typical Hall-Petch strengthening behaviour  Fe concentration in deposit not affected by pulse conditions  No definitive trend of hardness vs peak current density  Build up rates increased with increasing duty cycle but were below expectations, but increased with addition of conducting salts  Experienced Fe depletion problems with bath aging  Samples made for salt spray corrosion and taber wear tests

16. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 16 Phase II Optimization  Co-Fe-P alloy  Studied variation of electrical parameters, pH and metal ion/conducting salt additions  Managed Fe depletion with complexing and reducing agents  Cobalt chloride-ferrous sulphate bath chemistry with hypophosphorous acid addition  Results  Higher current densities increased Fe concentration in deposits. P content independent of current density  Fe content increased with pH; P content decreased with pH  Grain size decreased with increasing P content  Plating rate significantly increased (.002 to.005”/hour) by conductive salt addition (NaCI) and higher average current density; not increased by higher metal ion concentration  Samples made for salt spray corrosion and taber wear tests

17. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 17 Phase II Optimization  Taber Wear Screening Test Results  Tests performed per ASTM D4060, ASTM C501 and MIL-A- 8625F  Nanocrystalline Co and Co-P alloys have higher Taber indices  Nanocrystalline Co-Fe-P alloys show significantly improved Taber indices. Higher Fe and higher hardness better  60-70% Fe concentration represents limit for lowest wear coefficient

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19. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 19 Phase II Optimization  Salt Spray Screening Test (ASTM B117)  >1200 hour exposure evaluated to ASTM D610 galleries  Nanocrystalline Co and Co-P alloys performed very well. Heat treatment did not degrade corrosion performance. Thicker coating performed better  Nanocrystalline Co-Fe on Co-Fe-P alloys performed very poorly.

20. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 20 Note: Data for WC-Co, T400 and Hard Chrome per “Replacement of Chromium Electroplating Using HVOF Thermal Spray Coatings”, Sartwell et. Al.

21. EPA DOE DoD Strategic Environmental Research and Development Program Improving Mission Readiness Through Environmental Research SERDP Program 1152 DACA72-00-C-003 (8/30/01) 21 Phase II Next Step  Investigate alternative alloy additions  Co-Fe-Zn  Co-Fe-Zn-P  Co-Fe-W  Establish sliding wear performance  Procure fatigue and hydrogen embrittlement test specimens  grain size: 4 to 29 nm  VHN: 500-600 as deposited  Plating rate:.004 -.006”/hour  Salt water corrosion: Co ~20% Fe ~20% Zn