Keith Legg Outstanding technical issues HCAT Program Review August 2001 Toronto

Keith Legg Corrosion Last meeting status  Confusing results  Previous HCAT generic data and beach exposure showed HVOF better  C-HCAT showed same  US-HCAT LG JTP data showed overall HVOF corrosion looked worse, but uniform rather than pitted  Data from AFRL on cracking and corrosion Current status  Additional US testing done per Boeing methods  Canadian corrosion testing complete  Very interesting hydrogen embrittlement/stress corrosion cracking data

Keith Legg Coating integrity - last meeting Last meeting status  Integrity (spalling at high load) still a concern  Looked fine for commercial use  High compressive residual stress coatings looked good  concern over relying on stress  Indications of satisfactory performance from initial tests of new parameters developed at Hill by Jerry S  Big bar tests planned as unsure if small bars properly represent HVOF material Air Force and Navy have different requirements based on different use conditions  land-based vs carrier-based There are different testing philosophies  standard samples and coupon tests (lab procedures)  large axial samples (Big Bars) to measure response to applied stress (Navy)  large bend bars to simulate what happens in service (Air Force, Goodrich)  rig tests (OEMs - Messier-Dowty, Goodrich)  flight tests (airlines - Delta)

Keith Legg Good and not-so-good results: Looks as though performance requirements can be met. But, depends on thickness and on deposition parameters (how the coating is optimized) - to be discussed by Jean-Gabriel and Jerry Schell Good and not-so-good results: Looks as though performance requirements can be met. But, depends on thickness and on deposition parameters (how the coating is optimized) - to be discussed by Jean-Gabriel and Jerry Schell To be covered this meeting  Additional data on newly optimized Hill 0.005” ” WC-Co coatings (Jerry Schell, John Sauer)  Hill/ALGLE bend tests on A- 10 pistons  Additional data on 0.003” WC-Co coated at Southwest Aero  NAWC big bar high load, low cycle integrity tests  Rig tests (Messier-Dowty and Goodrich)  Flight tests Coating integrity - this meeting