A Spanish university, in collaboration with steel company ArcelorMittal, has successfully 3D-printed a lightweight steel frame.
Motorcycles News have reported that “the University of Nebrija and ArcelorMittal have succeeded in producing a steel frame using the 3D-printing process, which is very light, but also has the necessary stiffness.”
Sergio Corbera, a mechanical engineering student from the University of Nebrija, said “The ability to create hollow parts was the biggest unknown in 3D printing metal. We are talking about wall thicknesses between 0.8 and 1mm in the chassis.”
The superior rigidity steel offers compared to aluminium means that such thin wall would be impossible with the latter material, but without the hollow pipes and thin walls the frame would be too heavy.
Motorcycles News reports that an algorithm, which ultimately decided the geometry and shape of the chassis, was created with the data from the 3D-printed tubes. The design, Corbera says, gives the frame a good balance “that allows the bike to behave very well on the track,” according to their simulations.
Using a standard steel material - nothing special for the 3D-printing process that differs from what you might find in the trellis chassis of a major manufacturer’s bike - the project created a frame that weighs just 3.8kg, according to Paula Rodriguez, a research and development engineer at ArcelorMittal. She said, “A high-quality aluminium frame from the major motorcycle manufacturers does not weigh less than five kilos, while the other steel frames weight about six to seven kilos.” That is not an insignificant saving.
3D-printing steel frames is not a totally new concept. KTM started using the same process for their MotoGP components, including the chassis tubes, recently, and one of their engineers, Sebastien Risse, spoke to David Emmett at Motomatters about this at the beginning of last year. Risse spoke about the greater “flexibility” that 3D-printing allows in the manufacturing process, and also how he believes it to be the future of manufacturing for production bikes, as well as other industries. That, now, would appear to be closer to being the case.
Images of the chassis courtesy of Motorcycles News.
