Investigating the influence of shielding gas stability of laser polished Ti-6Al-4V alloy using image processing

Abstract

The use of Additive Manufacturing methods in modern manufacturing is increasing rapidly. However, the high surface roughness of the manufactured parts is a major drawback for Additive manufacturing methods. Therefore, additively manufactured parts need subsequent surface treatment. Laser polishing (LP) is one of the nontraditional polishing techniques, where a shielding gas is also used during the process to eliminate the adverse effects of the atmosphere. In this study, additively manufactured Ti-6Al-4V samples were laser polished by using Argon as shielding gas. During the operation, the flow stability of shielding gas was changed to observe the consequences of gas flow instability during LP. This observation was carried out by using Image Processing techniques. Even though surface quality alteration is possible even with an unstable gas flow, the output of surface modification may differ along with the material, especially in terms of surface roughness. The surface quality of the sample which processed under a stable Argon flow gave homogenous results, while the sample which processed under an unstable Argon flow gave non-homogenous results on its surface.

Keywords

• Laser Polishing
• Shielding Gas Stability
• Surface Roughness
• Surface Coloring
• Image Processing

References

1. 1. Ergene B., Simulation of the production of Inconel 718 and Ti6Al4V biomedical parts with different relative densities by selective laser melting (SLM) method. Journal of the Faculty of Engineering and Architecture of Gazi University, 2022. 37(1): p. 469-484.
2. 2. Yasa E., J.P. Kruth and J. Deckers, Manufacturing by combining selective laser melting and selective laser erosion/laser re-melting. CIRP Annual, 2011, 60(1): p. 263–266.
3. 3. Mohammadian N., S. Turenne and V. Brailovski, Surface finish control of additively-manufactured Inconel 625 components using combined chemical-abrasive flow polishing. Journal of Material Processing Technology, 2018, 252: p. 728–738.
4. 4. Ma C., M.T. Andani, H. Qin, N.S. Moghaddam, H. Ibrahim, A. Jahadakbar and C. Ye, Improving surface finish and wearresistance of additive manufactured nickel-titanium by ultrasonicnano-crystal surface modification. Journal of Material Processing Technology, 2017. 249: p. 433-440.
5. 5. Li J., W. Huayang, L. Haixu and Z. Dunwen, Surface and property characterization of selective laser-melted Ti-6Al-4V alloy after laser polishing. The International Journal of Advanced Manufacturing Technology, 2023. 127: p. 9-10.
6. 6. Wang Y., L. Yuhang and G.Yingchun, Surface modification and mechanical properties of laser powder bed fusion Inconel 718 after magnetic-assisted laser polishing. Optics & Laser Technology, 2023, 162.
7. 7. Temmler A., E. Willenborg E and K. Wissenbach, Design surfaces by laser remelting. Physics Procedia, 2011, 12: p. 419–430.
8. 8. Temmler A., E. Willenborg E and K. Wissenbach, Laser Polishing. Proc. SPIE 8243, Laser Applications in Microelectronic and Optoelectronic Manufacturing (LAMOM) XVII, 2012. 82430.

9. 9. Giorleo L., E. Ceretti E and C. Giardini, Ti surface laser polishing: effect of laser path and assist gas. Procedia CIRP, 2015, 33: p. 446–451.
10. 10. Temmler A., I. Ross, J. Luo, G. Jacobs and J.H. Schleifenbaum, Influence of global and local process gas shielding on surface topography in laser micro polishing (LμP) of stainless steel 410. Surface & Coatings Technology, 2020. 403.
11. 11. Cwikla M., R. Dziedzic and J. Rainer, Influence of Overlap on Surface Quality in the Laser Polishing of 3D Printed Inconel 718 under the Effect of Air and Argon. Materials, 2021, 14(6): p. 1479.
12. 12. Sun X., W. Wang, X. Mei, A. Pan, Y. Chen and J. Cui, High Capacity color code preapred on titanium alloy using femtosecond laser. Optics & Laser Technology, 2022, 145.
13. 13. Perez del Pino A., P. Serra and J.L. Morenza, Coloring of titanium by pulsed laser processing in air. Thin Solid Films, 2002. 145: p. 201-205.
14. 14. Perez del Pino A., P. Serra and J.L. Morenza, Oxidation of titanium through Nd:YAG laser irradation. Applied Surface Science, 2002. 197(198): p. 887-890.
15. 15. Perez del Pino A., J.M. Fernandez-Pradas, P. Serra and J.L. Morenza, Coloring of titanum through laser oxidation: comparative study with anodizing. Surface and Coatings Technology, 2004. 187: p. 106-112.
16. 16. Diamanti M.V., D.C. Barbara and P. MariaPia, Anodic oxidation of titanium: from technical aspects tobiomedical applications. Journal of Applied Biomater Biomechanic, 2011, 9(1): p. 55-69.
17. 17. Kurniawan K.F., I.M. Ulfah and K. Muhammad, The Effect of Anodic Oxidation Voltages on the Color and CorrosionResistance of Commercially Pure Titanium (CP-Ti). Evrimata: Engineering and Physics, 2023, 1(1): p. 18-23.