Color Printing on Titanium using Laser Cutter

Group Research Project for Spring 2024 CS 581 Computational Fabrication at Boston University

Group Members

Ruichen Liu

Lead the project group, did background research, designed experiment trails, wrote algorithms to generate bitmap files for testing and wrote a pipeline to convert a given image to corresponding bitmap file.

Qi Guo

Participate in the project with group classmates in Epic to control the laser cutter, give presentations in class, and write the report about motivation and related work.

Chenxi Yu

Conducted experiments on Epic, analyzing each result and meticulously documenting the parameters and experimental processes with team members. Responsible for the presentation and reporting of the fabrication section.

Introduction & Motivation

Anodizing titanium is traditionally achieved by heat/flame or electrolysis. In this project, we explore color printing using a laser cutter.

Approach

Initial Experiments

We first did several experiments to determine the optimal parameters for printing. We can control the power and speed of the laser cutter, and we want to find which combination of parameters produces the most vibrant color, and what colors the laser cutter can print on titanium.

60w laser cutter in EPIC

Printed color is lighter, and needs higher power.
Speed: 1%, Power: 60%, 80%, 100%
Speed: 10%, Power: 5%, 20%, 40%, 80%, 100%
Speed: 5%, Power: 100%

80w laser cutter in EPIC

Speed: 10%, Power: 45%, 55%, 60%, 65%, 75%, 90% Purple to blue
Speed: 5%, Power: 45%, 55%
Speed: 25%, Power: 50%
Speed: 15%, Power: 50%, 40%, 30%

Computational

After finding the 4 most vibrant colors we can print on titanium, we wrote an algorithm to map a given image into the 4 colors we have, and convert it to bitmap for the laser cutter to print.

Result

Computational

Original Yellow/Purple Dark/Light Blue
Solid
Stroke
Flowers * 4

Fabrication

Demo

Conclusion

In conclusion, we achieved our goal of determining the parameters for each color, and we successfully created a pipeline to convert a given image to corresponding bitmap image. The final fabrication result is also close to what we expected.
For future work, firstly we think a better quality laser cutter with finer control of the laser power and speed would produce better results, just as we saw in previous research[Antończak, A.J., Stępak, B., Kozioł, P.E. et al, 2014].
Secondly, we would wish to use better quality titanium plates, making sure all plates are cut from the same metal, eliminating any variables in the quality of each individual plate.

Acknowledgement

We would like to express our sincere gratitude to Professor Emily Whiting for her invaluable guidance, support, and encouragement throughout this course project.

We would also like to thank Sam Silverman, our Teaching Assistant, for his assistance and feedback, which have been crucial in the development and completion of this project.

Additionally, we extend our thanks to all our classmates for their advice and encouragement.

Finally, we want to thank the staff at BU EPIC; this project would not have been possible without their expertise with the laser cutter.

References

Antończak, A.J., Stępak, B., Kozioł, P.E. et al. The influence of process parameters on the laser-induced coloring of titanium. Appl. Phys. A 115, 1003–1013 (2014). https://doi.org/10.1007/s00339-013-7932-8

Emilio Latorre and Emily Whiting. 2023. Laser Polishing: A Postprocessing Protocol for Fused Deposition Modeling 3D Printed Parts Using Existing Tooling. In Proceedings of the 8th ACM Symposium on Computational Fabrication (SCF '23). Association for Computing Machinery, New York, NY, USA, Article 17, 1–3. https://doi.org/10.1145/3623263.3629154

Panotopoulou, A., Paris, S. and Whiting, E. (2018), Watercolor Woodblock Printing with Image Analysis. Computer Graphics Forum, 37: 275-286. https://doi.org/10.1111/cgf.13360

Trotec Laser USA. 2023, Let's Laser it: Color Marking and Engraving Titanium with a CO2 laser, YouTube. https://www.youtube.com/watch?v=T8_7BeqOX9c