Effects of Variable Amplitude Laser Scanning for Wire-Fed Metals Additive Manufacturing
Open Access
- Author:
- Walsh, Christopher
- Area of Honors:
- Engineering Science
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Abdalla Ramadan Nassar, Thesis Supervisor
Lucas Jay Passmore, Thesis Honors Advisor - Keywords:
- Additive manufacturing
AM
Laser processing
Laser scanning
Scanning
Metals additive manufacturing
Metals AM
Simulation
Laser characterization
Software development - Abstract:
- Metals additive manufacturing (AM) utilizing scanning laser optics is currently an under- explored topic, but has potential to offer greater process control and performance. One of the greatest drawbacks of AM is long processing times due to low deposition rates. However, optical systems that enable the rapid scanning of a high-power beam allow for more material to be deposited per unit of time. The introduction of a non-linear beam path creates more complex engineering problems to solve, but it also introduces more variables that can manipulated for greater control over the printing process. One such variable is the pattern of the scan path itself. By dynamically manipulating the scanning path of the beam, the imparted energy distribution to the substrate can be tailored however the process controller wants. For example, a pattern of linearly attenuating scan amplitude can configure material overlap when two beads meet at an angle. The calculated input energy, among other factors, can also be used to estimate the bead geometry. In order to predict the resulting imparted energy distribution, a series of software has been developed to characterize a high-power laser beam, generate a scanning pattered based on sliced CAD data, and iteratively simulate the energy imparted on the substrate using the properties of the characterized beam. Studied here is a hot wire-fed directed energy deposition (DED) AM system utilizing an ABB Robotics industrial arm with 6 degrees of freedom, an IPG Photonics continuous wave 12kW ytterbium fiber laser, and a Laser Mechanisms FiberScanHR laser scanning system.