Laser hot wire welding of multi-layered structures

A method of welding multi-layered metallic workpieces, the method comprising:

• providing a pair of multi-layered workpieces, each having a base layer formed over a cladding layer comprising a corrosion resistant element;
• forming a root pass weld bead to join the cladding layers of the workpieces using a first filler wire comprising the corrosion resistant element;
• forming one or more weld beads over the root pass weld bead to join the base layers of the workpieces by resistively heating a second filler wire while directing a laser beam over the root pass weld bead, such that a concentration of the corrosion resistant element in at least one of the one or more weld beads is less than 50% of a concentration of the corrosion-resistant element in the root pass weld bead;
• and
• forming a buffer weld bead between the root pass weld bead and the one or more weld beads, wherein the buffer weld bead is formed by resistively heating a buffer filler wire while directing another laser beam over the root pass weld bead, wherein the buffer filler wire has a different composition than the first filler wire and the second filler wire.