Laser cladding with extra fine wires
Fraunhofer IWS has developed the innovative laser processing head COAXwire mini for the processing of finest metal wires in surface cladding and AM. This head allows the production of metallic coatings and three-dimensional structures in small dimensions previously unattainable. It is the answer on the industrial request for efficient and resource-saving production methods. Surely, wire is a proven feedstock material in additive welding processes, but so far existing solutions allow only standard wires with a diameter of 0.8 to 1.2 mm.
The newly developed and patented COAXwire mini laser deposition head is now available for processing wires of 0.1 to 0.6 mm in diameter. It is based on the proven coaxial three-beam principle. It enables processing in all welding positions in a precise and omi-directional laser deposition procedure. Besides the system technology, current developments have also been focused on the qualification of the laser process specially for ultrafine wires below 0.4 mm. The result is a long-term stable process with wires down to 0.1 mm, such as those for wires with larger dimensions. In contrast to powder deposition in small dimensions, the material utilization is always 100 %, independently from wire diameter, welding position, and track geometry. An additional new feature is the increased range of suitable laser wavelengths. Lasers with 450 to 550 nm (green, blue) can be used like the common infrared lasers with 890 and 1100 nm. Thus, a broad spectrum of metallic materials can be processed efficiently. The integrated new wire drive unit guarantees a stable supply even of these extra fine wires.