Aachen partners develop low-cost SLM unit

07 Nov 2016

With a cost of around €30,000, the tool will debut at Formnext 2016 in Frankfurt, next week.

Aachen University of Applied Sciences (FH Aachen) and the nearby Fraunhofer Institute for Laser Technology (F-ILT) are presenting a new, low-cost selective laser melting (SLM) unit for the first time at the Formnext additive manufacturing expo in Frankfurt am Main, running between November 15-18, 2016.

Developed jointly with the GoetheLab at FH Aachen, the unit is designed primarily for small and medium-sized enterprises for which expensive selective laser melting technology is not yet economically viable because of the high level of investment required.

For major corporations, it is relatively easy to make the move into additive manufacturing (AM): they can hire specialists, invest in costly plant, or establish dedicated divisions. Industry, especially in Germany, however, is largely characterized by small and medium-sized enterprises. Recent studies by the German Federal Ministry for Economic Affairs and Energy show that there is insufficient awareness among SMEs of the potential of AM and the opportunities it offers.

Affordable 3D printing

This is where the Aachen Center for 3D Printing comes in. It was established by FH Aachen in conjunction with Fraunhofer ILT in 2014. “Our group of experts works closely together to give medium-sized companies access to 3D printing,” commented the center’s director, Prof. Andreas Gebhardt. The Center offers companies additive manufacturing training courses, advice, and services covering component design, manufacturing, and finishing processes.

A collaborative project has now developed a low-cost unit for SLM. Employing a Cartesian coordinate system, this first functional prototype uses a 140W laser diode with a focus diameter of 250 μm to produce complex metal components with a maximum height up to 90mm.

Entry-level

A unit with a comparable installation space costs at least €100,000, according to Dawid Ziebura, a project engineer at Fraunhofer ILT. He believes that the low-cost SLM unit will have a price tag of €30,000. Factors in its favor are that entry-level users need only a few hours to learn how to operate it, and that it is easy to use. “This low-cost unit makes it easy for entry-level users getting into 3D printing of metal components,” said Ziebura.

Typical components that the unit produces are suitable for SLM applications, ranging from prototypes and sample parts to functional components. The users themselves determine the speed and the production quality at which the unit operates. It can, for instance, produce a medium-sized (55cm³), stainless steel part (of grade 1.4404) at a density of more than 99.5% within 12 hours.

In addition, the unit offers the option of producing lattice structures for large-volume areas in order to shorten the construction time of less-stressed areas. Selecting a lattice density of 20% reduces construction time by 60%. The engineers in Aachen now want to shorten process times and optimize exposure strategies in order to improve component quality. They are planning to 3D print components made of aluminum alloys and tool steel.

Demonstration at formnext 2016

At formnext in Frankfurt am Main from November 15-18, 2016, prospective buyers can visit the Fraunhofer booth to see the new, low-cost SLM unit in action: Hall 3.1, Booth E60.