Naturally, we expect current 3D printing methods to continuously improve, but it continues to do so in the most surprising ways. The latest development comes from LEAM, a startup spun out of the Technical University of Munich (TUM), where the company’s cofounders developed a unique form of polymer additive manufacturing (AM) that overcomes one of the key disadvantages of existing forms of plastic extrusion: anisotropic strength.

With the firm’s Directed Energy Material Extrusion (DEMEX), a series of LED lights around a plastic extruder heats the material up to the optimal temperature before it is deposited from the print head. This allows it to bond seamlessly with the preceding layer, achieving the interlayer adhesion not found in traditional material extrusion technologies. This means that the Z-axis of the parts is just as strong as the X- and Y-axes, which has been the Achilles heel of common fused filament fabrication systems.

LEAM claims that DEMEX enables the 3D printing of proven, lower-cost materials by printing with injection molding grades, and even combine multiple materials in a single print—placing the right material in the exact spot it’s needed, despite being limited to a single extruder. Furthermore, the system facilitates the creation of parts through new process combinations, enabling the functionalization and individualization of carbon fiber reinforced polymers components or injection molded parts.

In developing the DEMEX process, the team also created a new temperature monitoring system that provides real-time temperature tracking and adjustments. It proactively identifies overheating, enabling adjustments such as active cooling or speed reduction to safeguard the print job, thus maximizing efficiency by allowing the printer to operate at the fastest possible speed without the need for pre-print temperature simulations. LEAM offers this technology as its own solution that can be incorporated into any existing large-scale extrusion 3D printer. According to the company, the temperature monitoring add-on can increase print speeds by up to 50 percent.

At the same time, this monitoring solution enables the creation of digital twins of every print job and part. All relevant machine parameters and the bonding temperature at every point within the component is recorded, as well as substrate temperature and print speed. By capturing this data, it may be possible to facilitate standardization and certification more quickly for critical applications in fields like oil and gas and defense.

Whereas DEMEX itself is exciting, it will be interesting to see how process monitoring expands beyond LEAM’s technology. As noted by multiple guests at Additive Manufacturing Strategies 2024, certification and standardization is one area that is holding back adoption of the technology in critical applications and industries. The sort of data that such a model as LEAM is offering may be the first step to creating such standards and ensuring that manufacturing operations are meeting them.

Images courtesy of LEAM and TUM. 



Source link

By GIL