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Field Touchup/Repair of Powder Coatings. Air Force Inventory Of OEM Powder Coated Equipment Continues to Increase Influence of success in commercial applications Performance Cost Environmental ComplianceAF Depot Level Powder Coating Capabilities Are Emerging Hill AFB Robins AFB Tinker AFB Others.
 
                
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1. Field Touchup/Repair of Powder Coatings 2003 Air Force Corrosion Program Conference
March 10  14, 2003
Dr. Douglas Neale
NCI Information Systems, Inc.
Mr. David Ellicks
Air Force Corrosion Prevention and Control Office
Robins AFB, Georgia
 
2. Field Touchup/Repair of Powder Coatings Air Force Inventory Of OEM Powder Coated Equipment Continues to Increase
 Influence of success in commercial applications
 Performance
 Cost
 Environmental Compliance
AF Depot Level Powder Coating Capabilities Are Emerging
 Hill AFB
 Robins AFB
 Tinker AFB
 Others
 
3. Field Touchup/Repair of Powder Coatings Powder Coatings Encountered
Thermosets  polymer powders applied electrostatically and baked (250oF  450oF)
Classes of powder chemistries for AF applications
 Epoxy  very good physical/chemical performance for
     interior use (UV-sensitive)
 Polyesters  very good physical/chemical performance for
    interior/exterior use
 TGIC
 Urethanes
Selection based on performance requirements and application characteristics of the coating 
4. Field Touchup/Repair of Powder Coatings How to Repair When Flawed or Damaged?
Requirements/expectations (depot and field)
 Repair process practicability
 Compatibility with existing powder coating 
 Performance  mechanical, chemical and 
    corrosion resistance (durability)
 Appearance
Production/depot sites
 Strip and re-coat entire part
 Touch-up (original process, aerosols, brush kits)
Field sites
 Original process not practical
 Touch-up with available military/commercial materials
 
5. Field Touchup/Repair of Powder Coatings Project Purpose: Develop Experience Base with Materials/Techniques for Field Repair of Damaged Powder Coatings
 Cleaning/preparation
 Coating materials
 Commonly available military/commercial products
 Innovative
 
 Application processes 
 
6. Field Touchup/Repair of Powder Coatings Project Elements
 Lab -  relative corrosion performance screening 
 Select common touch-up/repair coating materials
 Select simple application process/technique
 Evaluate relative corrosion performance
 Modified Q-Fog CCT-1 (common automotive standard)
 Cyclical corrosion
 4 hrs salt fog, 2 hours dry-off, 2 hours humidity 
 Down-select
 Field
 Environmental exposure of repaired coupons
Florida Coastal
 Repair damaged support equipment 
7. Field Touchup/Repair of Powder Coatings Laboratory Screening Tests
 Powder coating materials selected
 Epoxy
 Polyester TGIC
 Urethane polyester
 Substrates  clean
 Aluminum  no pretreatment
 Steel  iron phosphate Bonderite pretreatment
 Coupons supplied/prepared by commercial vendors
 Morton (Rohm & Haas)
 Sherwin Williams
 
8. Field Touchup/Repair of Powder Coatings Laboratory Screening Tests (continued)
 Repair materials
 Common MILSPEC primers/tie-coats/topcoats
 Commercial topical pretreatments/VCI coatings
 UV-cured topcoats
 Direct-to-metal waterborne acrylic latex topcoats
 Urethane protective barrier tape
 
9. Field Touchup/Repair of Powder Coatings Laboratory Screening Tests  Repair Materials
Solventborne primer / high solids topcoat 
 Baseline:  -23377, Type 1, Class C / - 85285, Type II
 -23377, Type 1, Class N / -85285, Type II
Waterborne primer / high solids topcoat
 -85582, Type I, Class C2 / -85285, Type II
Pretreat / high solids topcoat (-85285, Type II)
 Alodine 1132
 Sanchem Safegard 6100C or 13150A 
 T.O. 1-1-8 non-chromated epoxy tie coat
 Cortec VCI 386
 
10. Field Touchup/Repair of Powder Coatings Lab Screening Tests  Materials (cont.)
Solvent-borne primer / water reducible topcoat 
 -23377, Type 1, Class C /- 64159, Type II (Army CARC)
 -23377, Type 1, Class N / -64159, Type II (Army CARC)
Waterborne primer / water reducible topcoat
 -85582, Type I, Class C2 / -64159, Type II (Army CARC)
Pretreat / water reducible topcoat (-64159, Type II)
 Alodine 1132
 Sanchem Safegard 6100C or 13150A 
 T.O. 1-1-8 non-chromated epoxy tie coat
 Cortec VCI 386
 
11. Field Touchup/Repair of Powder Coatings Lab Screening Tests  Materials (cont.)
 Single coat 
 Cortec VCI 386
 UV-cure coatings (2 manufacturers)
 Stand-alone (no primer or pretreat)
 Over Alodine 1132 pretreatment
 Over Sanchem Safegard 6100C or 13150A
 Over Cortec VCI 386
 
12. Field Touchup/Repair of Powder Coatings Lab Screening Tests  Materials (cont.)
 Direct to metal acrylic latex (DTM)
 Stand alone (no pretreat)
 Over Alodine 1132
 Over Sanchem Safegard 6100C or 13150A 
 Over Cortec VCI 386
 3M 8681 HS polyurethane tape over pretreat
 Alodine 1132
 Sanchem Safegard 6100C or 13150A 
 Cortec VCI 386
 
13. Field Touchup/Repair of Powder Coatings Auxiliary Touch-up Coating Development
Corrosion Office initiative
Powders dissolved directly in environmentally compliant solvents (acetone, PCBTF)
Brush/aerosol application of coating with matched chemistry
Local thermal cure (heat gun, IR lamp)
Coating produced, properties under investigation 
 
14. Field Touchup/Repair of Powder Coatings Lab Screening Tests -  Coupon Preparation
Powder coating removal in center band (PMB)
Roughen bare metal and adjacent powder coating with polymer abrasive pad
Isopropyl alcohol wipe
Brush application of primer/pretreat and topcoat
 
15. Field Touchup/Repair of Powder Coatings Lab Results  General
 640 hours  80 cycles, Modified CCT
 All Touch-Up Coatings Proved Chemically and Physically Compatible with Substrates/Powder Coatings Evaluated
 Abrasive Pad/Alcohol Wipe Provided Suitable  Surface Prep (Coating and Substrate)
 Brush/Sempen Used for All Coating Application (Cosmetics Not Optimum) 
See Final Tech Report for Detailed Analysis 
16. Field Touchup/Repair of Powder Coatings Lab Results  Quantitative Evaluation of Coating Systems Used for Repair
 Numerical Composite Rating of Performance
 Creepage
 General Corrosion 
 Blisters
 MILSPEC Baseline Comparison:  -23377 / -85285   
17. Field Touchup/Repair of Powder Coatings 
18. Field Touchup/Repair of Powder Coatings Field Tests
 Down-selected Candidates from Original 	Matrix 
 New Coatings Identified After Start of Lab Tests 
 Battelle Florida East Coast Test Site
 Repaired Damaged Coatings on Coupons
 6 Month Exposure
 Evaluate Performance (Visual  Quantitative)
  Corrosion penetration, creepage
  Blisters
  Coating appearance
 Test Analysis/Report Due in March, 2003 
19. Field Touchup/Repair of Powder Coatings Field Tests -  Down-Selection from Original Matrix 		
 1:  -23377 Type I,  Class C / -85285 Type II
 2:  -23377 Type I,  Class N / -85285 Type II
 3:  -85582 Type I,  Class C2 / -85285 Type II
 8:  -23377 Type I,  Class C / -64159 Type II
 9:  -23377 Type I,  Class N / -64159 Type II 
 10:  -85582 Type I,  Class C2 / -64159 Type II 
 15:  VCI, Single Coat
 24:  Alodine / HS Polyurethane Tape
 26:  VCI / HS Polyurethane Tape
 28:  Alodine / Water-Borne DTM Acrylic Latex
 30: VCI / Water-Borne DTM Acrylic Latex 
20. Field Touchup/Repair of Powder Coatings Field Tests - Added Coating Systems
 T1:  DTM Acrylic Latex Primer / DTM Acrylic Latex Topcoat
 T2:  DTM Acrylic Latex Topcoat (Two Coats,  No Primer)
 T-3A:  Zero Rust  Primer (Aerosol)
 T-3B:  So Sure (Aerosol) 
 UV:  UV Cured Liquid Applied at Manufacturer Facility
 Z:  -23377 Type I, Class N / -85285 Type III
		    ( 50 mg/l VOC) 
21. Field Touchup/Repair of Powder Coatings Damaged Test Coupon Configuration
  
22. Field Touchup/Repair of Powder Coatings Field Test Results - Aluminum
  
23. Field Touchup/Repair of Powder Coatings Field Test Results - Steel
  
26. Field Touchup/Repair of Powder Coatings Conclusions  Lab and Field
  All coatings used for touch-up were chemically and 	  	 physically compatible with the powder coatings
  Scuff sanding and alcohol wipe provide good bonds
  Multi-component MILSPEC paint systems provide best 	 performance  available in small touch-up kits for field
  Non-chromated MILSPEC primers generally performed as 	well as chromated under MILSPEC topcoats
  HS polyurethane tape provides excellent protection
  UV cured liquid technology not ready for field
  Innovative powder/solvent not viable
  Powder coatings are not magic - current touch-up/repair 	 procedures and techniques apply for powder coatings  
 
27. Field Touchup/Repair of Powder Coatings Questions? 
28. MOPAF 
 
29. MOPAF 
30. MOPAF  PRAM PROJECT:
 TWO YEARS:  SEPT 01 -? SEPT 03
 PURPOSE:
 ACCELERATE IMPLEMENTATION OF POWDER COATING 
    TECHNOLOGY INTO AIR FORCE MAINTENANCE ACTIVITY
  DEMONSTRATE CAPABILITY ON MAJOR PRODUCTION 
     COATED COMPONENTS/EQUIPMENT
  PROMOTE ENVIRONMENTAL COMPLIANCE 
     REDUCE/ELIMINATE  HAZMATS, VOCS, HAZWASTES
 
31. MOPAF  PROJECT ELEMENTS:
 SURVEY/SELECT CANDIDATE PROCESS/STAKEHOLDER
  OGDEN ALC -  PRIMARY
  OKLAHOMA CITY ALC  - SUPPORT
 VALIDATE POWDER COATING PROCESS ON CANDIDATE APPLICATION
AIRCRAFT WHEELS
LANDING GEAR COMPONENTS
 DESIGN/BUILD/VALIDATE MODULAR FACILITY
IN PROGRESS
 IMPLEMENT MODULAR FACILITY AT STAKEHOLDER SITE
SUMMER-FALL  2003
 
32. MOPAF PROCESS VALIDATION:
MATERIALS:
 T-38 WHEELS - 2024 ALUMINUM ALLOY
 LANDING  GEAR COMPONENTS
 7000 SERIES ALUMINUM ALLOY (ACTUATOR)
 4340 HS STEEL (STRUT - 260 KSI) 
COATING SYSTEMS  COMPARATIVE PERFORMANCE TESTING
  SURFACE PREP
WHEELS  ANODIZED, PEENED/ANODIZED
LANDING GEAR ALUMINUM  ANODIZED
LANDING GEAR STEEL  CAD PLATE, IVD ALUMINUM
BASELINE: -85582 TYPE I CLASS C2 / -85285 TYPE I
 POWDER  TGIC POLYESTER (275OF CURE)
SINGLE COAT
-85582 PRIMER / P0WDER
 
33. MOPAF COMPARATIVE COATING PERFORMANCE TESTS
 CORROSION:  CCT, FILIFORM, B-117
 TENSILE STRENGTH (ALUMINUM)  5 BAKE CYCLES
 FATIGUE (ALUMINUM)  5 BAKE CYCLES
 HYDRAULIC FLUID IMMERSION  3 FLUIDS
 GRAVELOMETER IMPACT  @ ROOM, LOW TEMPERATURE
 TEMPERATURE SHOCK
 ABRASIVE RESISTANCE
 CLEANABILITY
 STRIPABILITY
 
34. MOPAF  EQUIPMENT SYSTEM DEVELOPMENT
 DESIGN
 BUILD PROTOTYPE 
 DELIVER/ASSEMBLE HILL AFB*
 FAMILIARIZE AF MAINTENANCE  PERSONNEL
 OPERATION/MAINTENANCE
 START- UP/VALIDATION
 INITIATE  PRODUCTION OPERATION
* FIRST ASSIGNMENT CONTINGENT ON SUCCESSFUL COATING PERFORMANCE TESTS 
37. MOPAF  CURRENT STATUS
 MOPAF CONSTRUCTION
 MARCH 2003 COMPLETION
 COMPARATIVE COATING PERFORMANCE TESTS 
   (@ CTIO)
 SPECIMEN PREPARATION:  INITIATE MARCH 2003
 CONDUCT TESTS:  JUNE -  AUGUST 2003 (ESTIMATE) 
38. MOPAF  REVIEW:
VERSATILE/TRANSPORTABLE MODULAR POWDER, CONVENTIONAL  COATING APPLICATION FACILITY
STAND-ALONE OPERATION AT A DEPOT OR FIELD SITE
INSTALLATION WILL NOT DISRUPT EXISTING PRODUCTION OPERATIONS
PROCESS VALIDATION  PRIOR TO COMMITTMENT TO POWDER TECHNOLOGY INTEGRATION OR CHANGEOVER
PRODUCTION USE DURING INTEGRATION/CHANGEOVER 
39. MOPAF QUESTIONS ??