EOS manufactures high-end industrial 3D printers, some of which can print in metal. But how do they maintain quality control?
A new partnership between EOS and MTU Aero Engines hopes to increase the quality of prints emerging from EOS’s line of 3D metal printers, including the M400, shown above. The two companies have pledged to work together to ensure the quality of engine parts produced by MTU Aero Engines with EOS equipment will meet required standards.
The process used by EOS’ equipment is powder based: a powerful laser traces selectively across a perfectly flat bed of fine metal powder, gradually fusing some of the powder into a solid layer. Subsequent layers are built on top to form a complete metal object.
There’s much more to it than simply moving the laser back and forth, as metal parts, particularly those used in aircraft, must meet critical mechanical property standards. The strength of a printed metal part, for example, depends not only on the type of material used, but also how the internal crystal structure forms. This result depends on a variety of features carefully built into EOS’ machines, such as ambient temperature, laser speed, material properties, and much more. Complicating matters further, all of this must happen within a sealed, oxygen-less chamber, lest the potentially explosive metal dust react.
The new quality control technology is an optical tomography (OT) process, described by EOS as:
In addition to several sensors that monitor the general system status, the camera-based OT technology controls the exposure process and melting characteristics of the material at all times, to ensure the optimum coating and exposure quality.
The ever-increasing quality of 3D printed metal parts from this vendor suggests that more manufacturing will be done with 3D printers in the future. It also may prompt other manufacturers to raise their quality game, too.