The underbody structure of the all-electric Cadillac Celestiq sedan consists of six large precision sand-cast aluminium parts. To realize the structures economically and as easily as possible, the American manufacturer of castings, Tooling & Equipment International (TEI), relies on additive manufacturing to produce all inner cores. For this, the US company is working with a German supplier of industrial 3D printers, Voxeljet. The printing system enables stiffening features of the hollow profiles that are not economically feasible with conventional manufacturing.
Each of the six sand-cast parts reduces the total number of components by 30 to 40 compared to a typical stamped structure, he said. Because each structural part has fully machined interfaces, the six castings can be assembled precisely, and tight tolerances can be maintained for assembly fabrication.
Each casting replaces up to 40 components
In the production of each vehicle underbody, the manufacturer needs a total of 51 additively manufactured sand cores. With the supplied 3D printing system, he prints hundreds of inner cores in one night. After printing, the cores are smoothed, coated with a fireproof coating, placed in sand molds and finally cast in a low-pressure filling process.Each of the six sand-cast parts reduces the total number of components by 30 to 40 compared to a typical stamped structure, he said. Because each structural part has fully machined interfaces, the six castings can be assembled precisely, and tight tolerances can be maintained for assembly fabrication.
