RECENT DEVELOPMENTS IN MELTING TECHNOLOGIES FOR TITANIUM ALLOYS

Stephen Fox TIMET

Titanium 2015 Orlando FL, USA

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Overview Expansion in melting capacity Cold hearth melting Vacuum arc melting Powder and Additive Processes Closing comments

Titanium 2015 Orlando FL, USA

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Expansion Drivers - Cost Ingot production up 30% since 2005 Global revert incorporation rates up significantly Dramatic increase in installed capacity capable of recycling

Source: Andy Bayne. International Titanium Association. Industry Supply Trends. Titanium Revert in 2015, September 2014, Chicago Illinois Titanium 2015 Orlando FL, USA

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Melting of Recycled Titanium

EB Facility (prior to 2005) EB Facility Installed/announced after 2005 EB Facility with expansion after 2005 PAM Facility with expansion after 2005 PAM Facility Installed/announced after 2005 PAM Facility with expansion after 2005 Skull Melt Facility (prior to 2005) Skull Melt Facility Installed/announced after 2005

Multiple Public domain sources Titanium 2015 Orlando FL, USA

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Overview Expansion in melting capacity Cold hearth melting technology Vacuum arc melting Powder and Additive processes Closing comments

Titanium 2015 Orlando FL, USA

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EB Melting VDM Metal Electron Beam Cold Hearth Melting Facility Source: J. Kiese, International Titanium Association, Titanium Europe, Birmingham, May 13, 2015

http://www.perrymanco.com /capabilities/melting

Titanium 2015 Orlando FL, USA

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Plasma Arc Melting

http://www.retechsystemsllc.com/plasma_melting/

Titanium 2015 Orlando FL, USA

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Skull Melting

Source: Matteo G. Ricci and Giampiero Santin, “Skull Melting Plant – A Stand Alone Facility for Melting of Titanium and Zirconium” Heat Processing (7) Issue 4, 2009. Titanium 2015 Orlando FL, USA

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Nearer to Shape Casting EB Hollow Casting Patented, proprietary process Semi continuous near to shape Heavy wall hollow ingot Products Hollow forging input stock Seamless Rings Extrusions Applications Energy – Down hole tubulars, risers, stress joints Industrial – large seamless rings Titanium 2015 Orlando FL, USA

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Update on numerical tools for EB cold hearth melting

Titanium 2015 Orlando FL, USA

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Solidification of EB Ingot True 3D problem • Asymmetric metal flow from inlet • Buoyancy driven flows • Momentum • Marangoni effects Top surface boundary conditions • Cooling to the environment • Electron beam heat input • Evaporation Side wall Boundary Conditions • Contact and cooling to the mold • Cooling to environment below mold

Titanium 2015 Orlando FL, USA

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Solidification of EB Ingot Predicted Temperatures during transient solidification stage of validation test ingot

Metal Inlet

Markers added during transient

Predicted Molten pool profile at end of steady state period. Note asymmetry

Model correctly predicts asymmetry of the pool, chemistry and last metal to solidify. Titanium 2015 Orlando FL, USA

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Overview Expansion in melting capacity Cold hearth melting Vacuum arc melting Powder and Additive Processes Closing comments

Titanium 2015 Orlando FL, USA

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Segregation in hypothetical VAR Current Status • Simulation of actual melt data • Assembly of multiple electrodes • Chemistry prediction • Melt profile development • Post melt process review and disposition Potential Future Developments • Integrating with look ahead control systems • Real time simulation as part of the quality record • Integration with “through process” simulation

Titanium 2015 Orlando FL, USA

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Dissolution of high nitrogen particles 10

5 mm particle 1 mm particle 0.5 mm particle

Size(mm)

8

6 0.6 4 0.55 0.5

2

0

5

10

0 0

50

100

150

200

250

300

Time(s)

• • • •

Particles close in density couple with liquid Residence time depends upon track High nitrogen feature will grow in size initially Dissolution controlled by diffusion of nitrogen Titanium 2015 Orlando FL, USA

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Overview Expansion in melting capacity Cold hearth melting Vacuum arc melting Powder and Additive Processes Closing comments

Titanium 2015 Orlando FL, USA

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Challenges - Transient Processes Gas Atomization - Electrode Induction Gas Atomization

Plasma Rotating Electrode Process

ALD AP&C Plasma Gas Atomization

• • • • • • • •

Rapid Heat input Complex and Rapid Heat Transfer Surface dominated effects Gas entrapment Satellites Shapes Shrinkage Size Distribution

AP& C Titanium 2015 Orlando FL, USA

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Challenges - Transient Processes PTA EB-Wire Feed Sciaky Warwick Manufacturing Group

Laser Freeform EB powder bed RPM Innovations ARCAM

Laser pwder Bed Siemens

AIM Challenge: Predict property variation from process data to speed up qualification Diverse Processes

Model Outputs

Increased Data Fidelity

• • • •

• • • •

• Physical properties for liquid and solid • Mechanical properties • Interfacial reactions • Solidification paths

Range of Scales Range of heat sources Range of heat input Range of feedstock

Microstructure Chemistry Stresses Shrinkage

Titanium 2015 Orlando FL, USA

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Closing Comments Melting Capacity has expanded Recycling through cold hearth and skull melt processes Computational methods increasingly important. Challenges for the future Integrating accurate process information Accurate prediction of critical structure Rapid and transient events associated with powder and additive processes Titanium 2015 Orlando FL, USA

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