1. D S Rickerby Rolls-Royce plc Derby, UK
The Future of Design for Surface Engineering in Aeroengine Applications
D S Rickerby
Rolls-Royce plc
Derby, UK
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

2. Contents The need for Advanced Materials
The move from reactive to proactive design of Material Systems.
Compressor
Turbine
Summary and Future Opportunities
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

3. Materials Making the Difference
“Developments in advanced materials, more than anything else, have contributed to the spectacular progress of the aero gas turbine”
Stewart Miller Director-Engineering & Technology
3rd Finniston Lecture 1996
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

4. Temperature capability
The Drivers
Strength
Temperature capability
Density
Cost
Time
Predictive
Capability
Performance
Safety
Weight
Noise
So we have looked at some of the impressive developments in efficiency, weight and materials over the past 20 years. But what is in the future?
Emissions
Cost
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

5. The Drivers Performance Safety Weight Noise Emissions Cost
Over the last 35 Years
Turbine Entry Temperatures have increased by 500C
In civil applications engine thrust has increased by a factor of x4
The specific fuel consumption has reduced by ca 35 %
Surface Engineering usage has increased from 25 to greater than 50 % for turbine components
Performance
Safety
Weight
Noise
Emissions
Cost
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

6. Trends in Materials Usage
Nickel
Titanium
Steel
Aluminium
Carbon composites 60 50 40 30 20 10
Weight Percent
1970
1980
1990
1960
2000
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

7. Titanium Fan Blade Snubber
Tungsten carbide/cobalt coatings reduce sliding/impact wear
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

8. Early Benefits of Surface Engineering – Corrosion Protection
Performance penalty of ca. 5% at take off which approached the limit of acceptability for a twin engined turboprop aircraft
Increase in specific fuel consumption of up to 2% which represented a significant cost penalty for the operators.
Surface engineering became an essential and very competitive issue in the aerospace industry.
Service run Nimonic 108 HPTB’s
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

9. Reactive versus Predictive Design
Resources Required
Revenue predictive design
Revenue Generated
Revenue reactive design
Time
Launch
Launch
Current and Future Designs
Predictive Design
Early Problem Identification
Solution when costs are low
Early Engine Designs
Reactive Design
High Costs
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

10. Product Definition Lifecycle
The aero engine market has never been more competitive
Mature industry, limited scope for technology advancement
Product differentiation is by being
First to produce a suitable engine for the market
Best specification to the customer
Engine development cycle in line with that of the civil airframers.
Four stage life cycle which covers all activities from the generation of the initial product concept and business case through to product entry into service and beyond into its service life.
Use of generic designs to existing and new products using proven technology.
Capability acquisition activity to secure future technology requirements
Slide says it all, but managed against the Derwent process to ensure robust technology introduction – which has elements of disposal of product in later stages but we only concentrate on the first four stages in this talk.
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

11. Product Definition Lifecycle
Business Led
Stage 1 Product Planning
Stage 2 Full Concept Definition
Stage 3 Product Development
Stage 4 In-Service Management
Capability Acquisition
MCRL/TRL
Preliminary Launch
Full Launch
Product Delivery
Development (1-4)
Pre-Production (5-6)
Production (7-9)
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

12. The Problem of Erosive Attack
Erosion can be caused by sand ,dust and even water.
It introduces uncertainty into any lifing assessment.
Severe erosion is generally confined to operation in specific flight areas ie desert type conditions.
The change in aerofoil geometry and liner dimensions will eventually impact upon engine performance.
The requirements for the coatings defined as:
No reduction in mechanical properties
Effective over a range of conditions
Retain component aerodynamics
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

13. Erosion Coating Service Experience
These early coating systems developed for use as hard wear resistant layers for machine tools.
Service return of blades showed deep scoring from impact of large particles causing local break up of coating.
Single layer systems do not give the required extension in life.
Need to develop coating systems tailored to their environment to give effective protection against erosion.
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

14. “Engineered” solution to erosion protection
Multi-layer coatings deposited using PVD methods to increase erosion performance – nano engineering
Impact on mechanical performance minimised
Capability being developed for advanced engines W
NiAl
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications

15. Multi-layer concept - GE T64 sand erosion tests
Service Performance of Multi-Layer Coatings
Description
Non-Coated
Coated
Rate of premature engine removal due to erosion
20-45% 0%
Rate of blade/vanes rejected due to erosion
70-80%
2-3% (mostly due to FOD)
Engine performance debit at overhaul
10-30%
<3%
Source: MDS-PRAD
IMFAIR Conference 10-11th June 2009
The Future of Design for Surface Engineering in Aerospace Applications