© WZL/Fraunhofer IPT

EDM and ECM processes for turbine engine manufacture Proposal for STC E Keynote 2014

Fritz Klocke, Andreas Klink WZL, RWTH Aachen University, Germany

Hongkong, 24th August 2012

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Motivation I/II

Quelle: Siemens, AgieCharmilles, Leistritz, MTU, WZL

ED

M

EC

M

Blade cutting W-EDM 3D ring structures, seal slots + cooling holes by S-EDM GE Blue Arc™ blisk machining

Blade production by ECM Curved cooling holes by ECM ECF Blisk production by ECM

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Motivation II/II

Quelle: KUL, IHI

Goal: Discussion on reachable …

Geometries

Material Removal Rates

Surface Integrity

in comparison to other machining technologies (cutting, grinding, Laser)

µ-E

DM

ED

M-C

oatin

g

Production of ceramic micro turbine via µ-EDM MS Coating and built-up technology

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Preliminary Outline Introduction and Motivation

Electro Discharge Machining (EDM) for turbine manufacture – Sinking EDM – Wire EDM – Arc machining (GE)

Electrochemical Machining (ECM) for turbine manufacture – Sinking ECM 3D – Cooling holes

Further EDM-ECM processes for turbine manufacture – Process combinations (EDM + ECM) – ECM-Grinding – Electropolishing – Micro turbines – Surface treatment (IHI)

Machine tools and CAD-CAM aspects

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6-axis-Sinking-EDM of radial compressor stage Rough machining: Turning

EDM of inflow and outflow sides

Finishing: Polishing

Quelle: sm-weber

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EDM in turbine manufacture

Quelle: Mühlbauer: Funkenerosion im Triebwerksbau, MTU, 2011

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ECM blade and blisk production

ECM blade machining

ECM blisk machining

Compressor blade

Guide blade

Quelle: Leistritz Turbomaschinen Technik GmbH

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Titanium blisk produced via ECM

Quelle: MTU-Aero Engines

Zweiteilige Elektroden

Titanblisk

Werkstoff:Vorschub:Titanbasislegierung1,5 mm/min

Spannung:Strom:13 V15000 A

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ECM and PECM Economic alternative

to milling

On the way to serial production

Blisk of nickel-based alloys

Very low efforts to smooth surface

Quelle: www.mtu.de/report, EMAG

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ECM of curved cooling holes Principle

Application

Quelle: Rolls-Royce, Köppern

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EDM, ECF and STEM production of cooling holes

Quelle: P. Thümmler, Herstellung von komplexen Kühlluftbohrungen in Hochdruckturbinenschaufeln, MTU, 2008

1th generation EDM

2nd generation Laser

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Electrochemical Fine Drilling ECF Material:

Nickel-based alloys

61 holes in one step

Length: 10 mm

Diameter: 0,5 mm

Quelle: MTU

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Comparison of different manufacturing processes for cooling holes

Quelle: P. Thümmler, Herstellung von komplexen Kühlluftbohrungen in Hochdruckturbinenschaufeln, MTU, 2008

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GE Blue Arc™ blisk machining 3 times of

material removal rate increase, 65% cutter cost reduction and 30% energy saving when applied to Inco718 as compared with conventional machining.

A video can be bound on youtube.

Quelle: B. Wei; A. Trimmer; Y. Luo; R. Yuan; S. Hayashi; M. Lamphere: Advancement in High Speed Electro-Erosion Processes for Machining Tough Metals, ISEM 2010

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MSCoating for Aircraft Engine Parts Micro Sparc Coating

Coating and cladding technology

Replace plating, welding and plasma spraying

Quelle: http://www.ihi.co.jp/msc/

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Technological + economical comparison of blisk roughing strategies

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Surface integrity comparison grinding – Wire-EDM Ground specimen

Eroded specimen

Crack path in an eroded specimen

500 µm

Thermally

influenced zone

Cracks

Material

break out

Deformed grains

Continously

thermally

influenced zone

Cracks

Thermally

induced marks,

shaped like shells

Crack path

Crack step

Black marks

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ECM machine tools

Machine framework: Polymer concrete MINERALIT®

Machine tool housing: stainless steel

Workpiece diameter up to 900 mm

Workpiece weight max. 500 kg

High positioning accuracy

Precise and flexible programmable oszillator

Grafic Visualisation

Scalable generator technology up to 30.000 A

Pulse frequency up to 100 kHz

Complex filtration

Quelle: EMAG ECM

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To be discussed … Literature

– Only 60 – 80 scientific papers expected…

– …but a lot of information from the industry could be available.

– Industry oriented KN like STC G 2009: „Industrial challenges in grinding“

Support from industry (corporate members) !?! – Pratt Whitney, AgieCharmilles, ExtrudeHone, … – RR, GE, MTU, Siemens, Leistritz, Mitsubishi, EMAG, …

Authors and Co-authors – F. Klocke, A. Klink (WZL) – …

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Thank you for your kind attention!