Trumpf is increasing the degree of automation and the process speed of its additive manufacturing technologies and, with the "green laser", is creating new applications for printing pure copper and precious metals. Klaus Parey, Managing Director responsible for additive manufacturing at Trumpf, says: "The market for additive technologies remains very attractive for Trumpf. In particular, our TruPrint 1000 with green laser beam source is attracting a lot of attention in industrial applications. Short-wave green laser light is the best choice for melting pure copper and precious metals."

Brake disks, hydraulic or sealing cylinders are components that are often provided with corrosion or wear protection. This metallic coating is achieved by laser metal deposition. Laser metal deposition (LMD) also delivers high-quality results and produces coatings that are virtually free of cracks and pores. The so-called area rate, i.e. the speed of the coating, is typically between 10 and 50 ^cm2/min in the standard LMD process. The high-speed variant of LMD, also known as EHLA, achieves between 250 and 500 ^cm2/min in an industrial environment. With a new nozzle technology, Trumpf has increased the area rate to well over 600 ^cm2/min. Depending on the application, speeds of up to 1,000 ^cm2/min are even possible. This is achieved with more powder, more laser power and a nozzle design suitable for industrial use. To achieve a higher surface application rate, you need more powder, which has to be melted quickly enough. This is why laser powers of up to 8 kW are required. This requires a robust, well-cooled nozzle. The new nozzle technology combines this interaction, which enables significantly higher area rates than before, especially for rotationally symmetrical components.

New de-powdering station increases purity level

To further increase productivity, Trumpf is optimizing the upstream and downstream work steps in the entire process chain. At Formnext, the company presented a new depowdering station for the powder bed-based Laser Metal Fusion (LMF) production process. It combines two process steps in one system: unpacking and depowdering the printed metal components. What was previously done manually by a machine operator with the help of suction nozzles and brushes is now easier and partially automated with the new depowdering station, especially for complex components. The system turns the finished printed component upside down and vibrates as required until the component is almost completely free of residual powder. The new de-powdering process therefore results in a higher degree of component cleaning. The machine operator is protected from harmful dusts, as the component remains in the chamber flooded with shielding gas until the residual powder has been removed.

Two years ago, Trumpf demonstrated at Formnext how pure copper and precious metals can be printed using a disk laser with a green wavelength. This is because copper and gold, for example, strongly reflect the infrared wavelength used in conventional 3D printers, making the melting process impossible. 3D printing of pure copper and precious metals is possible with shorter wavelength green laser light. The TruPrint 1000 Green Edition is now well established on the market. Toolcraft, for example, uses it to produce components for various industries, and the company C. Hafner uses it to build watch cases from red gold and platinum. The "green printers" are also running at full speed at the Fraunhofer IWS.