IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Titanium Contact Mechanics Increasing use of titanium led to the need to specifically investigate wear mechanisms, establish test methods and provide solutions. Basic wear mechanism simulated by simple hammer wear test and like versus like solutions introduced in the 1960’s onwards which offered low wear with intermediate friction. Continued developments to introduce low friction coatings appropriate to fan blade root fixings in the 1980’s. With the increased complexity of modern designs, dedicated rigs are used to understand geometry and service loadings.
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Fan Blade Low Friction Coatings
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications HH HH P P Q Q Q Q Fan Blade Low Friction Coatings Combined HCF/LCF cycles Representative of engine conditions (Load, frequency etc) Fretting wear Representative edge of bedding contact pressures / stresses Representative friction conditions Low loads, sliding conditions Point contact Unrepresentative of engine conditions Ranking test Button on Plate RigBi-axial Rig
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Advanced Sub-Element Testing Fan Blade sub-element test: captures geometry, surface condition and loading. Typical blade + Disc FE sector model Computer control: combined load spectra as in engine Low friction coatings give low transmitted load
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Composite Plating Disc Fin Seal Coatings Abrasive coatings used to control the degree of frictional heating during contact on disc fin seals. Works by cutting a clean path in the abradable liner. Rig testing showed that the application of the abrasive system significantly reduced the degree of heat generated during rubs
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Highly Instrumented Abradability Facility Alstom Abradability Facility Room Temperature Abradability Facility Located Rapperswil, Switzerland Capable of Blade and Fin Assessment Curved or Flat Test Piece Shoes Comparison of un-tipped with c-BN tipped nickel fins
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Increases in TET associated with progress in turbine materials and technology Year of introduction Turbine Entry Temperature K) Uncooled Blades Cooled Blades Coated Blades Demonstrator Technology Production Technology SX cast DS cast Cast Alloys Wrought Alloys W1 Dart Avon Conway Spey RB211 Trent Thermal Barrier Coatings
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Turbine Blade – Cooling and Coating Technology Uncooled Gas Temp: 825ºC Multipass Gas Temp: 1425ºC Thermal Barrier Coating Gas Temp: >1550ºC
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Source: R C Reed, Superalloys: Fundamentals and Applications, Cambridge University Press, 2005 Alloying Additions into Turbine Blade Alloys
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications TBC Bondcoat Design Ability to establish a pure alumina scale which exhibits a low growth rate Improved phase stability to reduce the influence of damaging substrate elements Bondcoat capable of replenishing the aluminium that is lost to alumina formation Bondcoat compatible with single crystal alloys and low parasitic weight No impact on the thermal mechanical fatigue properties of the TBC system Strength at high temperature to limit creep deformation No formation of SRZ’s on third and fourth generation alloys
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Potential for a System Design Optimisation Approach for Turbine Hardware
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Modelling Knowledge Base Computer System Materials Data Phase diagram model Property models Microstructural models Process model Cost model Design Tools Calculate process parameters and microstructure Calculate mechanical properties Improve and optimise Define the material and process Requirements Solution
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Governments, corporations, and venture capitalists spent more than $8.6 billion worldwide on nanotechnology R&D in Manipulating Atoms to Make Materials Nano Materials Nanograined alloys Structural materials Nanoreinforced polymers Coatings Tribology Hard Low friction Thermal Fire Retardant TBC Anticorrosion Low surface energy Smart Materials - Anticoking coatings The United States has appropriated over $4 billion for nanotechnology R&D since 2000
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Titanium metal matrix composites Conventional disk & blades Blisk - up to 30% weight saving Bling - Ti MMC - up to 70% weight saving EJ200 size TiMMC reinforced Bling
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Systems Design - Making the Difference Summary Requirement for “highly engineered” solutions Effective integration of materials and manufacturing technology. Continuity of funding/teams Taking time out of the material development process Extensive use of modelling/simulation to expedite material and process development Demonstrator opportunities Maintenance of key relationships with University network and throughput of skills
IMFAIR Conference th June 2009 The Future of Design for Surface Engineering in Aerospace Applications Predictive DesignReactive DesignToday FromTo Evolving design requirements Defined design requirements Extensive development trials Controlled parameters Product performance assessed by ‘ build and test’ Product performance modelled and simulated Empirical understanding Data driven environment Performance and producibility problems fixed after product in use Designed for robust performance and producibility Quality ‘tested in’ Quality ‘designed in’