Multi-Axis Metal Additive Manufacturing Without Support Structures

A collaborative team from Promation, ModuleWorks, and Multi-Scale Additive Manufacturing (MSAM) Laboratory of the University of Waterloo has developed and successfully tested a new method for manufacturing overhang geometries without the need for support structures. The tests were conducted at the University of Waterloo in Ontario, Canada using Laser Directed Energy Deposition (LDED). By eliminating support structures, the team was able to simplify process planning and reduce waste material.

Parts with geometric overhangs, such as pipes with bends, pose a special challenge for additive processes that deposit material in horizontal layers. To deposit material in the overhang area of the bend, the process needs to incorporate support structures that allow the layers to extend beyond the pipe. This works well enough but incorporating support structures adds time and effort to production planning and creates extra waste material.

To simplify and speed up the LDED process, Promation, ModuleWorks, and MSAM teamed up to develop a new method that deposits the layers in non-horizontal planes. The printing nozzle is mounted on a 6-axis robotic arm to ensure it always remains tangent to the deposition surface which is automatically tilted using a 2-axis positioner. Applying deposition layers to a tilted surface enables pipe bends and other overhang geometries to be printed without support structures, which simplifies production planning and reduces waste material.

In the laboratory tests, the team used the new method to manufacture a pipe with a 45-degree bend with no support structures. The new method was also used to successfully print a closed hollow dome.