Test Status Overview

HCAT Program Review NASA, Florida Dec 13,14, 2000 Keith Legg 847-680-9420

Rationale

  A lot of data has been generated in HCAT/CHCAT program in the past 3 or 4 months Aim is to show overall status - where we are in testing and what we have learned overall    Put current data in a logical order Address what we are doing to resolve some testing issues Suggest some “compartments” for existing and new data Keith Legg 847-680-9420

Overview

   Aircraft use of HVOF coatings Why are we doing this? commercial flight tests Overall status of JTP tests   JTP - Corrosion, wear, fatigue, embrittlement, impact Ancillary - Process specs, producibility, additional corrosion, additional fatigue, failure mechanisms    Conditions seen by real parts Summary of findings to date What does all this mean for actual usage?

  Where does it work just fine?

Where do we need to worry?

Keith Legg 847-680-9420

Flight testing Why are we doing this?

 Flight testing (Boeing, Delta, Lufthansa etc.) shows acceptable performance with no serious problems  Wear performance much better than chrome   no gouges, striations, flaking, etc. commonly seen in Cr better seal life if Ra~4  ” (rapid seal damage if rough)  some FPI crack pattern indications on Lufthansa aft inner cylinders (Barkhausen showed no crack penetration to substrate), nothing requiring removal from service Typical chrome damage - axle Keith Legg 847-680-9420

Production use of HVOF WC-Co and WC-CoCr coatings

Component Coating

Steering collars Slat tracks Pan castings Gimbals Bolts Wear rings Plungers Fittings Mufflers Fairings Landing gear sleeves, pins Boeing 747-400 landing gear Boeing 737 landing gear Airbus 320 landing gear F-18 Main landing gear axle HVOF, plasma, D-gun WC-Co HVOF, plasma, D-gun WC-18Co D-gun WC-14Co Plasma Cr 2 O 3 HVOF, D-gun, plasma Tribaloy 400 D-gun, plasma Cu 37Ni-5In, WC-18Co HVOF WC-CoCr HVOF WC-CoCr HVOF WC-CoCr HVOF WC-CoCr

Specific ation

BAC 5851 BAC 5851 BAC 5851 BAC 5851 BAC 5851 BAC 5851 BAC 5851 BAC 5851 AMS 2447

Notes

Boeing OEM coating Boeing OEM coating Boeing OEM coating Boeing OEM coating Boeing OEM coating Boeing OEM coating Boeing OEM coating Overhaul and repair Overhaul and repair Canadian Air Force – flight tested, in final approval Keith Legg 847-680-9420

Production use of HVOF WC-Co and WC-CoCr coatings (cont.)

Sikorsky CH-53 blade damper P&W F-119 Engine Convergent Nozzle Actuator Slat tracks, Boeing Bombardier Q-400 flap tracks Bombardier Q-400 and Global Express door stop pins Slat and flap tracks Flap track repair – Bombardier Dash 8 L1011 flap tracks Plasma T400 Super D-gun WC-Co and Plasma T400 Super D-gun WC-18Co HVOF WC-Co HVOF WC-Co HVOF WC-Co HVOF WC-Co HVOF WC-Co HS 4412 BAC 5851 Bombardier PPS 24.04 Bombardier PPS 24.04 Boeing 737, 757, 767 landing gear Parker-Hannifin actuators HVOF WC-Co Various BAC 5851 RD 8-57-1164 to 1169 BAC 5851 In final approval for Navy CH-53 fleet Hamilton Sundstrand spec. Engine likely to be used on JSF OEM usage OEM usage OEM usage Overhaul and Repair Overhaul and Repair Overhaul and Repair – Titanium alloy Main and nose landing gear O&R at Delta Airlines OEM usage – all new-design hydraulics  Qualified for landing gear repair <0.010” Keith Legg 847-680-9420

Production use of HVOF landing gear coatings - Messier-Dowty

Program-p/n Part name Type of coating F/A-18 E/F

74A430702 74A430616 Piston head assy Retract Actuator NLG Cover assy Gear/manifold Diamalloy 1004 (Al bronze) Applied per AMS2447 Tribaloy T400

F/A-18 C/D

74A410603 Head, Piston Shock Absorber MLGF-18 E/F Diamalloy 1004 (Al bronze) Applied per AMS2447

Hawker 4000

34520-1 REO 450626 01 74A410509 Lock link outboard forward door mechanism NLG Tube Restrictor Support Axle of the polygon WC-Co per DCMP 210 (AMS2447-7) AMS 2447-4 Ni95-Al5 AMS 2447-9

Cl601R J

17114-1 17207-1

A340 CLG

37173-101 37174-101 15173-101 15174-101

BD 100

40672 Shock strut piston MLG Shock strut pin MLG Sleeve thrust shock strut Pin, Piston Tube NLG WC-Co-Cr per DCMP 213 (AMS 2447-9) WC-Co-Cr per DCMP 213 (AMS 2447-9) Tribaloy T400 DCMP 203 (AMS2447-2) WC-Co-Cr per DCMP 213 (AMS 2447-9)

Area

6.612 OD 8.974 ID OD 0.866 OD

Remarks

Production part Production part R&O DRED Flat stops 2.623/2.621 OD Production part R&O 2.931/3.374 polygon In progress 4.614 OD 1.498 OD 2.348 ID Under evaluation in service by Air Canada, NIEO Under evaluation in service by Air Canada, NIEO Production part Production part  Note production use on high performance aircraft Keith Legg 847-680-9420

Data summary: Landing Gear JTP - Coupon test data

Data Item Corrosion Test

C-HCAT salt fog ASTM B-117 US-HCAT salt fog B117 US-HCAT cyclic salt fog GM 9540P/B

H Embrittlement

US-HCAT Deposition ASTM F-519 US-HCAT H Evolution ASTM F-519 US-HCAT Environmental Emb. ASTM F-519

Fatigue WC-Co (Hourglass)

US-HCAT in air 0.003" ASTM E-466 US-HCAT in air 0.010" ASTM E-466 US-HCAT corrosion ASTM E-466

Fatigue WC-CoCr (Smooth bar)

C-HCAT air 0.003" thick ASTM E-466 C-HCAT air 0.010" thick ASTM E-466 C-HCAT corrosion ASTM E-466 C-HCAT low temp. ASTM E-466

Impact

Dropped ball Gravelometry ASTM D-3170

Wear

Fretting GEAE Osc. piston/bushing Hydraulic simul.

Completeness 25 50 75 100 Pass Fail Notes x ???

???

Standard flat Modified sample. Retesting Modified sample. Retesting

x -

No embrittlement by HVOF No acceptance criteria

x x x

R=-1, 0.1

R=-1, 0.1

R=-1, 0.1

x ???

???

R=-1. Delamination above 180 ksi load R=-1. Delamination above 125 ksi load R=-1. Rapid corrosion initial tests

x

Data being obtained Equivalent or better than Cr Data complete - being analyzed Data complete - being analyzed Keith Legg 847-680-9420

Data summary: Propeller Hub JTP - Coupon test data

Data Item Test Corrosion

WC-Co, WC-CoCr, T800, Ni plate ASTM B-117

Fatigue (Hourglass)

WC-Co, T800, Cr ASTM E-466 WC-Co, T800 ASTM E-466

Wear

Large stroke and dither HSD

Toxicity leaching

WC-CoCr, T400, T800 waste EPA 1311

Completeness 25 50 75 100 Pass Fail Notes

Standard 4"x6" flat panel HSD hourglass, R=0.1

HSD notched hourglass, R=0.1

HSD wear plates Acetic acid leach Keith Legg 847-680-9420

Corrosion

 C-HCAT B117  JTP work complete  HVOF performed significantly better than chrome - Pass  US-HCAT B117  Initial test results reported in Ottawa, Aug 00  HVOF coatings worse than Cr - Fail  Appears to be a testing issue  Outstanding issues - resolution of US-HCAT results  Retesting under way  Different sealing - Boeing Cd method  2 different geometries (Flats and cylinders)  2 different deposition conditions (Southwest Aero, Hitemco)  2 different cabinets Keith Legg 847-680-9420

Embrittlement

  Tests partially complete  Sequence 1 - HVOF does not cause embrittlement - Pass   Sequence 2 - Not yet complete   H 2 can diffuse through HVOF coating May need longer bake Sequence 3 begun - no data yet Outstanding issues   Environmental embrittlement measurements in process Coating may lower Kt - calculations and tests under way at Heroux Keith Legg 847-680-9420

Fatigue - WC-Co

   WC-Co     US-HCAT testing complete All WC-Co air fatigue data equal to or better than Cr Pass All WC-Co corrosion-fatigue data equal to or better than Cr - Pass Delamination from some specimens at high cycles  WC-CoCr   WC CoCr 0.003” delamination at high load Pass below 180 ksi, Fail above 180 ksi WC CoCr 0.010” delamination at high load Pass below 125 ksi, Fail above 125 ksi  WC-CoCr corrosion-fatigue Fail??

Not a structural issue, but a functional issue (Messier-Dowty) Outstanding issues  Results of WC-CoCr fatigue testing  being addressed under Ancillary Testing Keith Legg 847-680-9420

Wear

  Fretting and sliding (hydraulic)  Data evaluation largely complete  HVOF better than or equal to Cr Rig and flight tests all show better wear performance   Less striation, wear, roughening (Delta, Greene Tweed) Less wear and leakage of seals (Greene, Tweed) Keith Legg 847-680-9420

Impact

  Drop ball testing  Under way Gravelometry (Boeing)  Completed - HVOF as good as or better than Cr - Pass Keith Legg 847-680-9420

Data summary: Landing Gear JTP - Rig and flight testing

Data Item Test Rig tests

Boeing F-18 LG pins Full scale Hydraulic testing Hydraulic M-D F-18 E/F NLG fat. Fatigue M-D F-18 E/F drag brace fat. Endurance BFG Dash-8/400 MLG Full scale BFG NLG steering act. Full scale BFG simulated piston fat. Full scale sim Boeing C-17 forward MLG Full scale

Repair scheme rig (Heroux)

CF-18 A/B NLG shock strut Full scale CF-18 A/B MLG crank assy Full scale CC-130 steering collar Full scale

Flight tests

Delta B737, 757, 767 LG M-D CF-18 polygon repair NADEP-JAX P-3 C-HCAT DND C-130 KC-135, MLG, NLG piston F-16 NLG

Completeness 25 50 75 100 Pass Fail Notes x x x x

HVOF pins included in rig test Greene, Tweed - long stroke and dithering spectrum Without catapult loads Rig complete, awaiting all test item parts Full scale piston fatigue simulation Durability - proposed. Out for coordination HVOF restrictor tube - compression, cyclic loading Torsion loads equivalent to landing loads Endurance life Internal Delta, not HCAT-sponsored Internal Messier-Dowty, not HCAT-sponsored C-HCAT testing Air Force - military typical worst case Air Force - high performance worst case Keith Legg 847-680-9420

Data summary: Propeller Hub JTP Rig and flight testing

Data Item Test Rig tests

54H60 low pitch stop lever sleeve Piston stroke

Flight tests

P-3 propeller 275 flight hrs

Completeness 25 50 75 100 Pass Fail Notes

WC-Co and T800 Tail shaft hub and sleeve lever Keith Legg 847-680-9420

Hydraulic testing - Greene, Tweed

2500 2000 1500 1000 500 0

Cycles (millions)

C hrome, Enercap Tribaloy, Enercap WC-C o, Enercap WC-Co-C r, Enercap Chrome, ACT Tribaloy, ACT WC-Co, ACT 4-9  ” Ra   PTFE (Enercap) much better performance with WC   low leakage low rod wear Elastomer rapidly damaged  not a problem with long stroke utility actuators and landing gear at 4 Ra Keith Legg 847-680-9420

Landing gear rig tests

  Boeing F/A-18 E/F landing gear pins  HVOF coatings “passed” full scale rig fatigue test  darkened, but no wear damage, passed MPI Outstanding - Additional full scale tests to be done by C-HCAT      Messier-Dowty F-18 E/F NLG fatigue Messier-Dowty F-18 E/F drag brace fatigue  including catapult loads BFG Dash-8/400 MLG BFG NLG steering actuator BFG simulated piston fatigue Keith Legg 847-680-9420

Flight tests

   Delta B737, 757, 767 nose and main landing gear  Inner cylinders, axles, axle sleeves  Passed WC-CoCr qualified for O&R Boeing 767-400  HVOF WC-CoCr flight qualified and used in production Canadian F-18 MLG  Messier-Dowty polygon rep air  WC-CoCr  Repair scheme approved  Outstanding - NADEP-JAX P3, DND C-130 testing Keith Legg 847-680-9420

Data summary Ancillary tests

Data Item Process parameters Test

US-HCAT WC-Co DOE C-HCAT NRC WC-CoCr DOE Commercial - SWA, Hitemco

Grinding/finishing

NADEP-JAX Delta Airlines Heroux

Stripping

NADEP-CP, S'west Aero CTC water jet Heroux

R&O Fluid compatibility

Heroux

NDI

Heroux Delta, Boeing flight tests

Corrosion

Beach exposure Salt fog B117 Cyclic salt fog GM 9540P/B US-HCAT comparison tests B117

Fatigue (Smooth bar)

US/C-HCAT WC-CoCr air ASTM E-466

Fracture mechanisms

C-HCAT NRC/Orenda

Specifications

AMS specs

Completeness 25 50 75 100 Pass Fail Notes x x x x x

Boeing QPL processes Low stress grind used on samples Used on flight test landing gear WC-Co and WC-CoCr strip w/Rochelle Incomplete stripping FPI, Barkhausen good; MPI poor Flat samples - generic tests Flat samples - generic tests Flat samples - generic tests New seal; flat, round, var. vendors, var. cabinets Powder, grinding, coating Keith Legg 847-680-9420

Process parameters

  WC-Co optimized by Jerry Schell by DOE methods  OO-ALC, Hitemco - JP 5000, DJ  Process designed for 8-12 Almen compressive stress WC-CoCr optimized by Jean-Gabriel Legoux, NRC by DOE methods    DJ-gun at NRC and VacAero Process designed for 8-12 Almen compressive stress Coating parameters different from QPL conditions used by Southwest Aero Keith Legg 847-680-9420

Grinding and finishing

     Overall finding - for seals need 4  ” or less Ra  Use fine grind or superfinish (specify other parameters?) Low stress grinding developed by Jon Devereaux at NADEP-JAX  used on all US-HCAT samples Surface measurement and superfinishing developed for landing gear by Jay Randolph at Delta Testing carried out by John Falkowski (Boeing) and Jim Nuse (Southwest Aeroservice) - AESF paper Additional testing under way  Boeing, SW Aero, Sulzer Metco, Engelhard, Praxair, Green Tweed, Supfina, Delta Keith Legg 847-680-9420

Stripping

     Water jet does not work very well Rochelle salt works well for WC-Co and WC-CoCr   SW Aero, Sulzer Metco NADEP-Cherry Point, NTS Testing at Praxair and others shows no embrittlement with strippers No good method for T400 yet Outstanding - need good chemical strip for Tribaloy Keith Legg 847-680-9420

Fluid compatibility

  Under way shortly at Heroux Will include evaluations of hydrogen embrittlement due to fluids Keith Legg 847-680-9420

NDI

     FPI best method so far  Delta, Boeing MPI not effective Boeing has used Barkhausen with some success Heroux testing begun Outstanding - how detect cracks in substrate without removing coating?

Keith Legg 847-680-9420

Corrosion

 All HCAT generic, C-HCAT, Lufthansa data on flats shows HVOF having better performance than Cr  US-HCAT Landing gear JTP data on rods showed worse than Cr - Fail  Repeating with better edge seal - comparing sample shapes, deposition conditions, test locations  Outstanding - Resolution of poor US-HCAT test performance (under way) Keith Legg 847-680-9420

Fatigue and fracture

 Fatigue of WC-CoCr - the picture folks took back from Ottawa meeting Keith Legg 847-680-9420

Fatigue and fracture

    Findings of cracking by AFRL (Bob Ware) Careful analysis done at NRC (Jason Dyer, Peter Au)  WC-CoCr fails, cracks and delaminates under high compressive load (R=-1)  0.003” coating, failure at 180 ksi and above  0.010” coating, failure at 125 ksi and above (note that thicker coating carries more load)  cracks grow down from coating surface and often run parallel to interface (similar mechanism to that designed into composites)  cracks do not appear to propagate from coating into substrate Surfaces of WC-CoCr fatigue specimens from Southwest Aeroservice also show crack pattern and some spalling at failure and runout This shows there may be operational limits of WC-CoCr Keith Legg 847-680-9420

Questions:

Where should we be testing?

What are the real-world requirements?

What are the functional limits of WC-CoCr and WC-Co?

Keith Legg 847-680-9420

Fatigue and cracking - historical

 Fracture data - John Quets, Shane Arthur  WC-Co initially designed

using bend test cracking data

  WC-CoCr designed to have better corrosion performance, but

lower fracture strength

So, WC composite coatings

balance

hardness and wear resistance against brittleness (fracture strength) 1998 - Crack-like indications found by FPI on aft side of WC-CoCr coated Lufthansa landing gear. Barkhausen analysis by Boeing showed no crack propagation into steel. Returned to service - no reported problems.

Bend test of Praxair WC-CoCr. Reported by Jay Randolph, Delta Airlines, July 1998 Keith Legg 847-680-9420

Landing gear design and fatigue testing

 Designers do

not

design to specimen test data  Coupons provide stress engineers the data to start analyzing for customer and air-worthiness justification  Difficult to translate from load on full scale item to stress on test coupon  Qualification always depends on full-scale item fatigue testing under spectrum loading to 2 or 4 lifetimes  Bulk of public domain data for AerMet 100 was run at 150 ksi or less (Roger Eybel)  a few points were run higher for interest sake Keith Legg 847-680-9420

Fatigue - Loads on Landing Gear

Name

Gary Erickson Roque Panza-Giosa Craig Edwards Boeing Commercial BFG GA/Air Force Roger Eybel Dave Weldon Michael Kane Michael Kane Nihad Ben-Salah

Company

Messier Dowty Messier Dowty NAVAIR NAVAIR Heroux

Maximum stress (kpsi)

170 180 180 150 211 180 240

R ratio

195 0.1, -1 207 0.1, -1 225 0.1, -1

Sample type

0.1 Large hourglass -1 -1 Actual LG A100 test specimens Full scale gear Test specimens Test specimens Test specimens Test specimens Test specimens

Notes

Vendor qual test Al alloys 20ksi 180kpsi is once-in-a-lifetime event. 135 normal use Bulk of public domain data - some at higher load for interest only Drag Brace Trunnion Pin Test - max bending stress Limit Ultimate (P3, E6, V22) Design Ultimate (high performance) 4340 (90% of yield) 300M (90% yield) A100 (90% of yield) Keith Legg 847-680-9420

Fatigue - Loads on Landing Gear

   Makes no sense to test coatings above levels used in full rig tests Looks as though we have the following maximum needs:    Commercial 170 ksi, R=0.1

Military, typical 180 ksi, R=-1 Military, high performance 240 ksi, R=-1 Questions:   At what loads/cycles were F-18 landing gear qualified?

Do you really go to yield thousands of times?

Keith Legg 847-680-9420

Summary of major ongoing work

    Corrosion  Additional tests planned  samples made Fatigue  C HCAT testing 0.003” WC CoCr below 180 ksi  Rethinking tests for 0.010” WC-CoCr  Comparative testing with SW Aero WC-CoCr and WC-Co Embrittlement  Environmental embritt.

Ball impact - in progress    Producibility testing  Heroux - grinding, stripping, NDI, fluids, etc.

Rig testing  BFG, Messier-Dowty Flight testing  NADEP-JAX P3  DND CC-130 Keith Legg 847-680-9420

Remaining issues being resolved

  US-HCAT corrosion testing to be redone  obviously testing problem Fatigue testing     Not a structural issue that will cause failure, but a functional issue that will impose limits Clearly define fatigue limits and requirements  Understand strain-to-failure, fatigue, residual stress relationships Definition of load/thickness limits for WC-Co as done for WC CoCr WC-CoCr with hourglass specimens to define S/N curve comparable with WC-Co per JTP?

Keith Legg 847-680-9420

Where does qualification look good?

    Commercial  no brainer - in production Military - general   likely to work with WC-Co may be near edge of envelope for WC-CoCr High performance military (primarily fighters)  need to define operational loads carefully to match qual of existing gear  may need lower hardness, higher toughness material Full article tests - rig, flight Keith Legg 847-680-9420

Remaining issues

   US-HCAT corrosion testing to be redone  obviously testing problem Fatigue testing of WC-CoCr with hourglass specimens  define S/N curve comparable with WC-Co per JTP Definition of load/thickness limits for WC-Co  as done for WC-CoCr Keith Legg 847-680-9420