Objectives

• Develop knowledge basis for new wires for welding of aluminium alloys, using nanoparticles for grain refinement and particle strengthening
• Develop laser beam/laser-arc hybrid welding of dissimilar metals (e.g., Al- Fe, Al-Ti, Al-Cu)
• Develop laser-arc hybrid welding for heavy steel (process-microstructures-properties
• Develop AM and cladding laser assisted processes

Approach and methodology

• Weld thermal simulations (Gleeble)
• Nano-/microstructure characterization of joints and rapidly solidified /AM components by light microscopy, SEM (incl. EBSD and elemental mapping), MicroProbe analyses, and TEM 
• In-situ heat treatment in SEM/EBSD and TEM/SPED
• Nanoparticle-matrix interface study and nanoparticle chemical stability
• Utilize advanced image analysis and apply machine learning methods 
• Use tomography techniques to extract 3D information

Challenges

• Steel welding: Welding of heavy steel is challenging with lase-arc hybrid welding. Double-sided welding may induce problems with keyhole stability.
• Aluminium welding: Strength loss in soft parts of the heat affected zone (HAZ) represents a major challenge in aluminium welding. Both HAZ and weld metal will be addressed through adjustments of the welding process and the addition of nanoparticles, respectively.  For additive manufacturing (AM) of aluminium alloys there is an urgent need for new wires and powders for direct energy deposition (DED). 
• Cladding: Silicides may have excellent corrosion and wear resistane, but have very limited applications so far. Tungsten carbides deposited by thermal spraying has dominated this business. More knowledge is needed on silicides as coating and actual coating processes will be important.