HCAT Propeller Hub Chrome Plate Replacement Program

Aaron Nardi - Steve Pasakarnis

Hamilton Sundstrand- Materials Engineering

Coatings Characterization Testing Contacts

• Fatigue - Steve Pasakarnis• Wear - Aaron Nardi• Corrosion - Blair Smith, Aaron Nardi• TCLP - Folashade Anderson• Low Pitch Stop Lever Sleeve, Sub-Component

Test - Ed Faillace, Folashade Anderson

Fatigue

• Covered in fatigue presentation on Wednesday morning by John Sauer

Wear Testing• Coating Types

• WC-Co

• WC-Co-Cr

• Tribaloy T-800

• Chrome Plate (AMS 2406)

• Nickel Plate (AMS 2423)

• Conterfaces• 4340 Steel

• Beryllium Copper

• Viton Seal Material

• 15% Glass filled PTFE

• Test Variables• Contamination Iron oxide, silica sand, Arizona Road Test

• Oil Type (Mil-H-83282, Mil-H-87257) Drip on each specimen

• Stroke Length- Full Stroke and Dithering

• Load

• Surface Finish

Wear Test Fixture

Load Pin

3000 lb. capacity

Spring Washers

Pivots

Coated Panel Specimen

Flat Counter-face Specimens

Wear Testing Results

• Quantitative Results– Weight loss and wear depth ( profilometer )results being measured

– Data not yet reduced

• Qualitative Results– Chrome plate exhibited the most extensive pitting when dithering

against steel with contaminated Mil-H-83282

– Chrome plate exhibited the most extensive adhesive plowing against the Be-Cu samples

• phosphate lubricants in Mil-H-83282 will only lubricate iron based alloys

– Neither HVOF WC-Co or T-800, exhibited pitting or adhesive plowing to the extent of the Chrome Plate in any samples tested, with WC performing the best overall

Dithering Tests With Steel Counterfaces in Contaminated Mil-H-83282

Hard Chrome Plate WC-17Co HVOF T-800 HVOF

Stroking Tests With BeCu Counterfaces in Clean Mil-H-83282

Hard Chrome Plate WC-17Co HVOF T-800 HVOF

Corrosion Testing

• ASTM B-117 Testing• Checked panels on a daily basis• .001, .005, .010” coating thickness on

coupons• Testing ground vs. as sprayed surface• Removal from tank criteria was:

– 3 or more spots– Spot bigger than 1/4”

Results From Corrosion Testing• Nickel Plating was the overall top performer• WC-Co-Cr was marginally the best HVOF coating• In General, the thick coatings performed better than

thin coatings• Machined specimens generally performed worse

than panels in the as coated condition.e to substantial corrosion

• Photos are worst case-coated panels showed– Co and CoCr showed varying results from panel to panel– T800 results were very consistent across all panels

• Trends were similar across the thickness ranges

As Coated Nickel Corrosion Panels

W-1, 8 days, 0.001 Thick W-6, 8 days, 0.005 Thick

As Coated Tribaloy T-800 Corrosion Panels

T-1, 5 days, 0.001 Thick T-2, 5 days, 0.001 Thick T-3, 5 days, 0.001 Thick

As Coated WC-Co Corrosion Panels

W-1, 12 days, 0.001 Thick W-2, 8 days, 0.001 Thick W-6, 20 days, 0.005 Thick

As Coated WC-Co-Cr Corrosion Panels

WCR-1, 20 days, 0.001 Thick WCR-2, 8 days, 0.001 Thick WCR-3, 8 days, 0.001 Thick

TCLP Testing Results

• Spent Material Tested (WC-Co-Cr, T-400, T-800)• Virgin Powder Tested (WC-Co-Cr, T-400, T-800)• NOT HAZARDOUS WASTE• In Connecticut Would Be Considered Non-

Hazardous Regulated Waste

Rig/Component Testing• Rig test of low pitch stop lever sleeve

component– Part experiences 10 cycles per flight and

testing will accumulate sufficient cycles to correspond to 7500 hrs of flight (i.e. overhaul interval)

– Loading will simulate actual flight conditions using hydraulic fluid at 150 degrees and pressure of 310 psi

Program Milestones

• Wear Testing - April 2001• Fatigue Testing - April 2001• Corrosion Testing - Complete• TCLP Testing - Complete• Component Testing -

– Testing to begin April 2001

• Flight Test - Start September 2001– Navy to Define Test Location