Abstract: A method of welding metal components together including moving a laser beam in a first direction along an interface between a pair of metal components such that in the vicinity of the focused beam, metal from each component is vaporized to produce a keyhole in a pool of molten metal. The laser beam is oscillated in a direction different from (e.g., transverse to) the first direction such that the keyhole oscillates through the pool of molten metal and molten metal fills into the keyhole as the position of the keyhole changes. A laser welding apparatus achieves oscillation of the laser beam using optical elements in the path of the laser beam, for example trepanning optics located within an expanded portion of the laser beam.

Abstract: The addition of a steel and titanium carbide mixture is laser melted on a steel surface in air or in a shielding gas having a significant nitrogen content. The resulting steel surface has improved hardness and bead shape.