Fraunhofer Institute for Material and Beam Technology IWSCOAXpowerline - the innovation for laser beam cladding processes
The processing head COAXpowerline follows the COAXn system. However, as a laser hybrid processing head, it is especially designed for very efficient coatings on large areas. The main feature here is that the laser powder cladding process is enlarged by an additional inductive heating. This kind of cost-saving additional energy helps to reduce temperature gradients and compensates heat conduction losses in the cold basic material. Consequently, high coating rates can be realized to such a degree that they can be compared to those, achieved with Plasma-Powder-Arc-Welding (PTA). The advantages, due to the laser, (low intermixing, high precision, decisive structures) remain untouched.
Application
COAXpowerline processing heads are applied in the field of large-area surface protection of components and tools. Apart from high cladding rates and a good profitability, the large-area coating has special demands to wear and corrosion characteristics. Even at a low laser power of 4 kW (Diode laser) ,combined with the cost-saving inductive support, we could realize cladding rates, which usually demand laser powers of at least 8 to 10 kW. Nevertheless, it is possible to use the processing head without the inductive module, e.g., at high laser powers < 8 kW. Corrosion coatings for cylindrical components in offshore areas or hard metal armoring for equipments in the oil and gas production are current application fields.
Technical data
The principle is an annular gap powder nozzle, so that it is completely independent from any direction. The induction modules are integrated into the processing head and can be easily adjusted to special tasks. Even an independent, additional inductive heating is available. The applied MF generators should have 20 to 50 kW.
- powder: commercial metal and carbide powder with grain sizes of ±20-125 µm
- pPneumatic mixing of up to 4 single powder components
- robust, inner media feed (powder, gas, water)
- diameter of the powder focus: 1.5 to 2.5 mm
- cladding rate (e.g. INCONEL 625) up to 18 kg/h
- standard gas: Argon, 5 to 8 l/ min
- preferably Diode laser up to 15 kW
- laser focus diameter: 4 to 10 mm