The fast track to series production

The ExAM 255 multi-material 3D printer can be used across materials (metal, plastic, ceramic) and processes (hybrid components). Compared to powder bed processes or other 3D printing processes that use materials with filaments, the CEM process systems achieve tensile strengths that come close to classic thermoplastic, mold-based injection molding. The price advantage with 3D printing is striking when commercially available granulates are used instead of filaments. When using granulates, the CEM process results in price advantages of up to a factor of 10.

Competitiveness in 3D printing with granules

The use of pellets in 3D printing with plastics is proving to be particularly competitive for components with fibers. In general, a distinction is made between fiber-reinforced (GF) and fiber-filled (if only short fibers are used). Two materials are of particular interest due to their prevalence in the plastics processing industry: PPS GF40 (polyphenylene sulphide) and PA6 GF30 (polyamide). They combine outstanding mechanical properties with media and temperature resistance.

As a so-called pellet printer, the ExAM 255 uses commercially available pellets, which are also used in injection molding technology. This means that 3D printing using the CEM process is very competitively priced compared to conventional manufacturing strategies. Depending on the material group, the price advantage in material cost for a processed component is between 80% and 96%. Such components usually have a higher density with high tensile strengths. According to the supplier, there is also a high degree of flexibility for the processor, as the material does not have to be modified. Identical, certified material means the same or comparable properties, such as thermal conductivity, media resistance, damping, mechanical properties, shrinkage or density. In addition, long fiber reinforcement with a fiber length of up to 3 mm is possible, with a filling level of up to 60%.

According to the company, another characteristic of the ExAM 255 system can be seen in the material cross-section of PA6 GF30: It offers high consecutive fidelity of the fiber orientation with the extrusion paths (pressure of filling/infill +45º/-45º). The web control can be used during printing to optimize the strength of the component. The cost-effectiveness is due not least to the favorable machine hour rates and the high energy efficiency of the 3D printing system.

The ExAM 255 also achieves accuracies of up to 25µm, depending on the build speed of course. The level of precision on the component is a result of the design: two pellet extruders work in the ExAM 255's installation space, which are supplied with material via separate feedstocks. The build chamber itself measures 255 x 255 x 255 mm³ and can be passively heated up to 60ºC. The build rate (with a 0.4 mm nozzle) is specified by Aim3D as up to 40 cm³/h, depending on the material selected.