Abstract
Interest in multi-axis additive manufacturing has grown significantly in recent years due to associated benefits that range from improved quality to support for greater geometric complexity. A method of 5-axis Laser Hot-Wire Directed Energy Deposition is developed and demonstrated in this study using an 8-axis industrial robot, comprised of a 6-axis serial link robot and a 2 degree‐of‐freedom positioner. Coordinated 5-axis motion is used to print Ti-6Al-4V objects predominantly through build plate rotation. Methods of slicing and toolpath generation are presented, including the use of an alternating toolpath direction philosophy and the manipulation of the CAD model surface normal vectors for determining the required build plate tilt angles for maintaining consistent deposition orientations relative to gravity. Another objective of the study was to determine the limits of conventional slicing and layer height control techniques for printing geometries with significant unsupported overhangs. A comparison is made between the behavior of normal and conformal bead alignment in this regard, and the performance of the layer height controller is reported as it relates to process stability and the limits of printing overhang geometries. Unsupported overhangs were successfully printed at 35° without build plate tilt and 45° with build plate tilt. Toolpath velocity and net-shape printing performance are reported as well, with 3D scans of the printed surfaces used for net-shape characterization. In all, the printing of three geometries is presented, including the overhang geometry, a 5-axis toolpath geometry, and a large-scale, multi-bead demonstrator part, which exceeded 500 mm in height and weighed 44 kg (97 lbs).
| Original language | English |
|---|---|
| Article number | 103048 |
| Journal | Additive Manufacturing |
| Volume | 58 |
| DOIs | |
| State | Published - Oct 2022 |
Funding
This research was funded by the U.S. Department of Energy , Office of Energy Efficiency and Renewable Energy , Advanced Manufacturing Office , under CRADA NFE-15–05725, in partnership with GKN Aerospace, USA. The authors would like to acknowledge the contributions of the extended Oak Ridge National Laboratory and GKN Aerospace teams, particularly those of James Haley, Alex Roschli, and Jeremy Malmstead of ORNL and Chad Henry and Chris Allison of GKN Aerospace. This research was funded by the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Advanced Manufacturing Office, under CRADA NFE-15–05725, in partnership with GKN Aerospace, USA. The authors would like to acknowledge the contributions of the extended Oak Ridge National Laboratory and GKN Aerospace teams, particularly those of James Haley, Alex Roschli, and Jeremy Malmstead of ORNL and Chad Henry and Chris Allison of GKN Aerospace. This manuscript has been authored by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this manuscript, or allow others to do so, for United States Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan (http://energy.gov/downloads/doe-public-access-plan).
| Funders | Funder number |
|---|---|
| Alex Roschli | |
| U.S. Department of Energy | |
| Advanced Manufacturing Office | CRADA NFE-15–05725 |
| Office of Energy Efficiency and Renewable Energy | |
| Oak Ridge National Laboratory |
Keywords
- 5-Axis
- Directed energy deposition
- Laser
- Robotics
- Slicing
- Titanium
