Additive manufacturing technologies for metal parts are mainly used for high-prized applications like prototyping. GEFERTEC GmbH introduced the new GTarc machines, which are able to manufacture metal parts cost-efficiently and at high production speed. The 3DMP additive manu-facturing technology is based on well proven electric arc welding and uses wire as original material. The final part is formed by applying welding layer over welding layer.
Compared to other additive manufacturing technologies, which are based on powder as original material, 3DMP is less expensive. Most standard materials are available as wire at lower prices. GTarc machines manufacture near-net-shape metal parts at high quality stand-ards, which are comparable to standard manufacturing methods. Only the finishing of the near-net-shape part is undertaken using standard CNC milling.
An example of an actual part – a bearing holder of nickel-chromium steel 1.4305 – demonstrates the cost-effectiveness: In conventional manufacturing a block (452 mm x 245 mm x 100 mm) weighing 85 kg has to be milled on a CNC machine. The final part weighs only 18 kg, thus, more than 80% of the material is converted into chips. The total cost amounts to 4,500 Euros as a result of 1,000 Euros material costs and 3,500 Eu-ros milling costs. In contrast, an 3DMP near-net-shaped part weighs 25 kg and can be produced on the GTarc machine for 750 Euros. Subsequent milling amounts to 1,250 Euros and produces only 28% chips. In total, these 2,000 Euros therefore represent a savings of more than 50% compared to conventional manufacturing. Although this comparison is based on estimated costs, which may vary depending on the company, it proves the potential of the additive 3DMP technology.
The GTarc machines are available in three versions. The 3-axis version GTarc 3000-3 is able to produce parts up to 3 m3. With an additional pan-tilt-table the 5-axis version GTarc 800-5 is suitable for parts up to 0.8 m3. The 5-axis GTarc 60-5 machine is for parts up to 60 l and 200 kg.
A 3DMP CAM software calculates the data out of the CAD model, enabling the CNC-control unit to position the welding head with high precision. The machine produces the near-net-shape part fully automatically. The costs of the GTarc machines are comparable to a small CNC milling centre. This additive manufacturing technology is suitable for fast and economical production of larger parts made of steel, nickel, titanium, or aluminium.