3D printing has become a serious alternative to ablative processes such as turning and milling in industry. 32% of industrial companies were already using the technology in 2019, twelve percent more than in 2016, according to a study by the industry association Bitkom. And user demands are increasing. "In recent years, more and more designers have asked us whether it is possible to manufacture components from several plastics using 3D printing in order to achieve special properties," says Tom Krause, Head of Additive Manufacturing at Igus.

The solution is two-component printing (2K). This allows tribo-filaments to be combined with carbon fiber-reinforced filaments, for example. The customer not only receives a low-wear component, but also a resilient one.

2K 3D printing: hardly any restrictions from a geometric perspective
"We have now expanded our 3D printing service to include so-called two-component printers (2K), which can work with two different printing materials and therefore enable greater flexibility in product development." The 2K printers work with the FDM process. The two molten plastics each flow through their own printing nozzle. The 2K printers can switch between the materials at any time during printing; they fuse at the transitions.

"From a geometric point of view, there are hardly any restrictions," explains Tom Krause. "The materials can surround each other, interlock with each other and alternate in layers." The only exception is when the melting temperatures of the filaments differ greatly and no material fusion is possible. In this case, designers can create a form-fit connection - such as a dovetail that connects two areas made of different plastics.

"This flexibility was previously impossible in 3D printing"
The filament portfolio includes lubricating and high-performance plastics with fire-retardant, hygienic and antistatic properties, among others. Tom Krause: "With the 2K printers, we have the option of combining the properties of two filaments in one component." One example of a two-component part is a gripper element for a machine that screws on lids in the food industry. The body is made of an Iglidur filament, which guarantees robustness and wear resistance, while the surfaces are made of a flexible material that ensures slip resistance. "With this 2K component, the user benefits from a mix of materials," emphasizes Tom Krause. "Previously, the individual parts could only be printed out and assembled one after the other. Now it's much easier and quicker." as