The Materials and Advanced Manufacturing Research Group ( MOD3RN ) at Nebrija University in Madrid has created a motorcycle frame by 3D printing it from powdered steel - the result is lighter than conventional designs made from aluminum or even titanium . Backed by steel producer AcelorMittal , the project uses readily available materials in the form of powdered steel and known 3D printing technology , using lasers to selectively fuse the material together in layers , building up the entire frame in a series of slices . The challenge was to meet the rigidity requirements of a motorcycle frame while using the absolute minimum amount of material . The project had to develop computer |
algorithms that allow the operator to enter details of key hardpoints of the chassis - the engine mount positions , for instance , and the steering head and swingarm pivot location - as well as the required level of rigidity . The computer can then work out a layout of frame struts that meets those requirements |
and which can be 3D printed with the least material . It is the latter part of the process that is critical - the frame struts are all hollow , with walls between 0.8 mm and 1 mm thick , and normal 3D printing would require those hollow areas to be filled with support structures . By placing the frame struts at particular angles , and orienting the frame correctly during the print process , the Nebrija algorithms eliminate these supports , significantly reducing weight . Sergio Corbera , engineering director at the university , said : " The possibility of generating hollow parts was the main unknown in metal 3D printing . We are talking about wall thicknesses of between 0.8 and 1 mm in the chassis . This involved addressing several issues |
within 3D printing : stability of the piece during the printing process as a result of the very low thicknesses , control of porosities and mechanical properties in these thicknesses , and orientation of the geometric shape to avoid internal supports ." The resulting prototype frame , designed to suit a single-cylinder race bike , weighs just 3.8 kg , compared to around 5 kg for a similar frame made from aluminum using conventional processes . A normal steel trellis frame of the same size would be 6 to 7 kg . |