Materials Joining R

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Materials Joining RD at Oak Ridge National
Laboratory

• Capability
• Arc, resistance, laser, laser assisted arc,
  electron beam, friction and robot welding, and
  brazing processes.
• Tools
• Thermomechanical simulator, weldability testing,
  weld vision-systems and residual stress mapping.
• Characterization
• Advanced characterization including analytical
  electron microscopy, atom probe tomography,
  synchrotron and neutron diffraction.
• Modeling
• Computational thermodynamic and kinetic models,
  property models, microstructure models,
  artificial neural network models and integrated
  weld process models.

http//mjndeweb.ms.ornl.gov
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ORNLs materials joining capabilities span a wide
range of applied research programs.
Resistance Spot Welding

• Energy Research
• Space Power
• Aerospace
• Automotive

Arc Welding
Brazing
Prototype ceramic-metal engine valve
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Fundamentals of materials joining are being
investigated to develop a science base.

• Nonequilibrium solidification in welds
• Microstructure evolution
• Phase stability kinetics
• Properties
• Welding consumables
• Residual stresses

Nickel base single crystal welds are being
studied using solidification theories.
Nonequilibrium g precipitates in rapidly cooled
nickel base superalloy are characterized using
atom probe tomography.
Liquid-Oxide thermodynamic equilibria describe
inclusion formation in welds.
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Advanced computational and analysis techniques
are being used to develop optimum materials
joining solutions.
Synchrotron diffraction is used to monitor
nonequilibrium phase transformations.
Thermodynamic and kinetic modeling predict phase
stability in welds.
Gleeble thermomechanical simulations track
solid-state phase transformations.
Artificial neural network model describes weld
pool shapes.