3D printers that build small parts layer by layer from melted plastic can take up to an hour to produce a pocket-sized piece. This process is far too slow for the mass-production of components as required by the automotive industry, for instance.

The SEAM process achieves ultra-fast production speed by combining 3D printing with the motion system of a machine tool. (© Fraunhofer IWU)

Researchers have developed an additive manufacturing system that takes only 18 minutes to produce a plastic component that is 30 centimeters high. The printer uses the Screw Extrusion Additive Manufacturing (SEAM) process that achieves these high process speeds by combining machine tool technology with 3D printing.

To process the plastic, a specially designed unit melts the raw material and ejects it at a high output rate. This unit is installed above a construction platform that can be swiveled in six axes using the motion system of a machine tool. The hot plastic is deposited in layers on the construction platform; the motion system of the machine ensures that the construction panel slides along under the nozzle in such a way that the previously programmed component shape is produced. The table can be moved at a speed of one meter per second in the X-, Y-, and Z-axes and can also be tilted by up to 45 degrees.

This experimental component is a hybrid of CFRP sheet metal and 3D-printed structures. SEAM makes it possible to print on injection-molded components or sheet metal. (© Fraunhofer IWU)

Every hour, up to seven kilograms of plastic are pressed through the hot nozzle with a diameter of one millimeter. Comparable 3D printing processes, such as Fused Deposition Modeling (FDM) or Fused Filament Modeling (FLM), usually achieve only 50 grams of plastic per hour. A unique feature is that, instead of expensive FLM filament, SEAM processes free-flowing, cost-effective, standard plastic granulate into resilient, fiber-reinforced components that are several meters in size. This method allows material costs to be reduced by a factor of 200.

SEAM allows implementation of complex geometries without supporting structures. The system even makes it possible to print on existing injection-molded components. Since the construction platform can be swiveled, the machine can print on curved structures with a separately moving Z-axis.

In tests, a wide variety of plastics could be processed, from thermoplastic elastomers to high-performance plastics with a 50 percent content of carbon fiber.

For more information, contact Jan Müller at +49 371 5397-1462, or visit here  .