Building shapes out of powder and wire
Deposition welding is a generating process for surface finishing as well as the repair and modification of existing components. Depending on the task at hand, either manual or automated laser deposition welding is used.
Laser Metal Deposition (LMD) is an additive process where a laser is used to melt metal powder or wire on to a substrate.
Manual laser deposition welding
In the case of manual deposition welding, the welder guides the filler material "by hand" to the area to be welded. A thin wire with a diameter between 0.006 and 0.02 inches is primarily used as filler material in this process. The laser beam melts the wire. The molten material forms a strong bond with the substrate, which is also melted, and then solidifies leaving behind a small raised area. The welder continues in this fashion, spot by spot, line by line, and layer by layer, until the desired shape is achieved. Argon shields the work process from the ambient air. Finally, the part is restored to its original shape by grinding, milling, turning, EDM etc.
Automated laser deposition welding
In automated deposition welding, the machine guides the filler material to the area to be welded. Although the material can also be a wire, this process primarily uses metal powders. Metal powder is applied in layers to a base material without pores or cracks. The metal powder forms a high-tensile weld joint with the surface. After cooling, a metal layer develops that can be machined. A strength of this process is its ability to build up a number of metal layers.