We recently caught up with the GE Additive Lichtenfels Process & Materials team to learn about their focus and recent work on aluminum parameters.

Tell us about the team

We currently have 15 engineers in our team at the new GE Additive Lichtenfels facility, locally known as the 3D Campus. Local is the keyword here. In fact, most of our team graduated from universities in the local area. A combination of different skill sets and disciplines, including materials engineers, process engineers and mechanical engineers mesh well to help us solve the diverse tasks we’re charged with.

As for our day-to-day right now, our biggest focus is on parameter development, where we fine tune and adjust the machine settings of our additive machines, like the laser power or scan speed, to get the perfect part outcome for the different materials we process. We get involved in customer projects in either a consultative capacity or working on specific parameter development. We also support our production and service teams by troubleshooting any issues that might occur.

As part of the GE Additive Global Materials & Powders team, we take part in weekly tech forums. This exchange helps us tap into all the expert knowledge from around the world and share our own experiences. Ultimately, this helps us all drive the best outcomes on the various projects we are all involved in.

We are also regularly involved in initiatives across the other GE businesses. We currently have multiple projects running concurrently with GE Aviation, focused on tailoring parameter sets, and projects with GE Global Research (GRC), which are focused more on the additive technology process, rather than the end-product.

Can you share more on the team’s work on processes and parameters?

Think of our team as organized into two parts. The first is the process part where the engineers work closely with the machine teams – for example the gas flow, optics and software teams – to understand how the characteristics of those systems drive the final part performance. We also support tasks such as specification definition, so whenever a new component is developed, we need to give our input from a process perspective. We then get involved with the design and consulting phase and the validation phase for either new machines or new subcomponents within a machine.

The other side is the materials part where we investigate how the laser parameters affect the microstructure of the material and tailor parameters to meet our customers’ requirements, like porosity, microstructure or mechanical properties.

When we combine these aspects and use the input from both groups of experts, this enables us to guarantee best part quality and material performance.

The team’s work on aluminum parameters has gained a lot of interest and praise from across the industry. Why is that?

We have quite a large parameter portfolio for aluminum alloys, which was even increased and improved by the most recent work and latest parameter developments. Work on aluminum parameters was done on all types of machines. Two projects were running for the AlSi10Mg, one on the M2 Series 5 and one on the X Line 2000R. The outcomes of these projects are high-quality parameter sets for this alloy.

Another project worth mentioning on the M2 was initiated to develop a high-productivity parameter set for AlSi7Mg. In the end we were able to more than double productivity compared to the previously available parameter set by increasing layer thickness from 60 to 90 µm and using the full 1kW capability of the machine while keeping part properties on a similar level.

Beyond these core alloys, we are also working on the high-strength alloy A205 for elevated temperature applications. We just recently released a parameter for our M2 machines, and we are currently at the stage of transferring the processes and parameter sets to our new M Line solution to get this material running well on that new system.

The team in Lichtenfels has historically been focused on laser technology. Do you also support our other modalities?

As we briefly mentioned, as a materials community we all come together in our regular tech forums to exchange ideas and knowledge. Being focused on the laser business, we have our own perspectives; however, whenever there are tasks to solve from a material point of view, it is always good to get an outside perspective. If we are working on material-specific problems or projects, such as heat treatment developments and microstructure evolution investigations, the modality is less important than the fundamental materials science knowledge, so we regularly speak with the EBM and Binder Jet teams to facilitate this materials science-focused crosstalk.

Can you tell us about the set-up of your new labs, and the on-site testing and analysis technology at your disposal?

There are three labs here at Lichtenfels:

  • The metallographic lab is where we do the cross sectioning and the etching (to visualize the melt pool shapes). We have several optical microscopes and one scanning electron microscope equipped with one EDS (energy dispersive X-Ray spectroscopy) and one EBSD (electron backscattered diffraction) sensor, which we use to do in-depth characterizations on the phases and chemical composition of a material.
  • The mechanical lab – where we do the tensile, hardness, and surface roughness testing (optical and tactile) – enables us to execute all the required standard testing methods. We also have one CMM (coordinate measuring machine) to check dimensional accuracy of parts. 
  • We also have a completely new powder lab where we can do almost everything related to powder characterization—from particle size distribution by laser diffraction to sieve analysis, flow testing and rheology testing using flowmeters. We built a special powder test rig to investigate the spreading and packing behavior of the powder to determine how the powders will behave in our machines. We also have the capability to analyze the chemical composition of powders and parts for different gases—including oxygen, hydrogen, nitrogen—as well as the carbon and sulfur content.

These new advanced material characterization capabilities are needed to satisfy the needs of our customers

GE Additive Lichtenfels materials lab - November 2021
Left to Right: Johannes Stroessner, Christopher Schunk and Dominic Graf, GE Additive Lichtenfels Process and Materials team

What value do in-house analysis capabilities bring to our technology and to our customers?

We do everything in-house, from sample preparation to characterization and heat treatments, and this reduces the lead times dramatically. Instead of weeks of turnaround time when using external labs, we are talking about a few days to get the results out of our own lab. In addition to the time benefit, it also significantly reduces the administrative effort required by the team.

The quick turnaround times are even more important for issues that might occur in production or in the field. Instead of sending samples away and waiting for an answer, we are able to immediately address issues when they come up.

Another aspect is cost. It is costly to perform metallurgical investigations, so by having direct access to the person doing the analysis and being able to influence how the samples are analyzed, you can really cut back on both time and cost compared to sending the samples to a vendor. This is extremely helpful as it not only accelerates but also improves the outcome of the analysis.

What gets you excited about materials science and additive?

Dominic Graf: The variety of work. We are not only directly developing different parameters, but we also collaborate closely with a lot of other departments of the business, like hardware design or software development across our portfolio of machines. I believe our wider Global Materials & Powder team is the link between the different R&D teams. We work with them to finish any development on our machines, we are also the first testers of new developments, and provide feedback regarding the changes and potential impacts on the process.

Essentially, our job is to improve the different additive manufacturing processes and machines so that we can ensure a high part quality. We do this by having that regular exchange, collaboration, and interaction with other engineering departments to generate different ideas and solutions to the challenges that present themselves each day. And there are still so many open opportunities to investigate or to improve, which makes our daily work so fascinating.

Daniel Rommel: One of things that is motivating for most tasks that we get is that we often do not have a solution immediately available. It’s our job to think about it, test, create and present a solution.

For me, that is more inspiring than simply getting a task assigned where you already know what to do. Here in Lichtenfels we are really focused on creating solutions for specific customer requirements, and that is both motivating and fascinating for the team.

Johannes Stroessner: I find it extremely helpful to get a connection to the product through a “touch and feel” experience. With the direct contact with what the machines are producing, we get direct feedback on how our developments impact the overall result. So, whatever you change, you directly see the outcome of the continuous improvements we make and, in turn, how it helps customers either improve the quality of their parts or produce them faster. 

It’s very easy here to make a tangible link between the materials science and our machines, and then eventually a connection to the end-product, and that is a very rewarding part of the job.

Overall outlook

The Lichtenfels team is a core part of the global materials organization within GE Additive that understands the whole additive process chain—from the powder through to the final part.

The diverse backgrounds, knowledge and skills within the team, coupled with new analytical characterization capabilities and a link to GE’s wider material science expertise, enables the Lichtenfels team to support both customer engagements as well as internal GE initiatives to facilitate the best possible outcome.

If you’d like to learn more about the Lichtenfels team and the wider GE Additive materials community, please get in touch