Researchers at Graz University of Technology have created a new type of 3D printer that uses LED instead of laser sources for additive manufacturing of metal parts. The new 3D printer can optimize 3D metal printing for construction time, metal powder consumption, device costs, and post-processing work. The team behind the 3D printer has applied for a patent on the technology.
The 3D printer uses technology said to be similar to Selective Laser or Electron Beam Melting. The process uses a metal powder that is melted and then built up to form a component. The new technique is called Selective LED-based Melting (SLEDM) and eliminates two central problems with powder bed-based manufacturing processes.
Those central problems include the time-consuming production of large-volume metal components and the time-consuming manual reworking. SLEDM uses a high-performance LED beam that features LEDs specially adapted by lighting specialists Preworks and equips the complex lens system that allows the diameter of the LED beam to be focused.
The lens system allows the beam to be changed between 0.05 and 20 mm during the melting process. The changeable LED focus allows larger volumes to be melted per unit of time without having to do filigree internal structures. The lack of internal filigree structures reduces the production time of components and fuel-cell or medical technology production by a factor of 20.
The process also means that in contrast to other metal melting systems, the component is assembled from top to bottom, leaving the component exposed and reducing powder required to a minimum. Necessary post-processing can be carried out during the printing process. Currently, the printer is being used to produce bioresorbable metal implants, such as screws made of magnesium alloys used two treat broken bones. Those implants dissolve into the body after the fracture grows together, eliminating the need for a second surgery to remove the screws.