Office National d’Étudeset de Recherches Aérospatiales

www.onera.fr

Dr. Stefan DRAWINONERA (French aerospace research centre)

Metallic Materials and Processing Department 92320 CHÂTILLON (France)

Ultra High Temperature Refractory Metal Based Ultra High Temperature Refractory Metal Based SilicideSilicide MaterialsMaterials

For Next Generation TurbinesFor Next Generation Turbines

Presentation OutlinePresentation Outline

• Introduction

• The project

• Alloy systems

Manufacturing

Mechanical properties

Oxidation resistance

Machining

• Conclusion

Introduction: increase engine performanceIntroduction: increase engine performance

• Environmental impact

efficiency (SFC, …)

emissions (CO2, NOx, …)

noise

• Reliability

• Costs

Long term goals (from ACARE):• 20% reduction in SFC • 80% reduction in NOx emissions• 50% reduction in CO2 emissions

(Rol

ls-R

oyce

)

Introduction: increase temperature capabilityof materials

Introduction: increase temperature capabilityof materials

• Increase thermal efficiency• Increase combustion temperature

(cfm

i)

through

• Advanced engine architectures

• Advanced cycle designs

• Novel combustor designs

• Optimised aerodynamics

• New cooling concepts

• Increased airfoil material temperature capability

+ 50°C in TIT ⇒ 4 – 5 % reduction in SFC

Introduction: increase temperature capabilityof materials

Introduction: increase temperature capabilityof materials

Introduction: what materials for turbine blades?Introduction: what materials for turbine blades?

Capabilities of turboengine materials, up to the most recent generation of single-crystal Ni-base superalloys

The ProjectThe Project

ULtra high Temperature MATerials for Turbines

• Develop Mo- and Nb silicide-based multiphase alloys• Develop cost-effective fabrication processes, based on PM or IM• Design coatings with improved oxidation resistance• Establish a database to benchmark against current materials, and

provide data for specific turbine operating conditions• Identify the critical material properties, processing requirements

and other factors (cost, etc.) governing production feasibility• Manufacture prototypes to validate machining and joining

processes• Carry out a preliminary assessment to introduce these materials in

high-performance turbines, and study implications for future component/turbine design

The projectThe project

ULtra high Temperature MATerials for Turbines

• Started: January 2004• Duration: 48 months

ONERA (coordinator) France

University of Magdeburg Germany PLANSEE SE Austria

IRC– Univ. of Birmingham UK Turbomeca France

University of Surrey UK University of Nancy France

Snecma France Walter Engines Czech Republic

Electricité de France France Rolls-Royce UK

Avio Italy

• 12 partners• 6 countries

Alloy systemsAlloy systems

Key properties

tensile creep (< 1% in 125 h at T > 1200 °C and σ > 175 MPa)tensile strengthRT toughnessoxidation resistance (∆e < 25 µm in 100 h at 1300°C)fatigue behaviour

andphase stability at T > 1300°Cdensity < 7.5 g.cm-3

processing at industrial scale

Replicate the properties of superalloys (∼1100°C)… at T ≥ 1300°C

Properties of alloys are governed by:

• composition

Alloy systemsAlloy systems

• microstructure

• various microstructures• various processing routes

• fast composition screening• small alloy batches