Investigations on color quality improvement through laser-induced surface oxidation for coloration

This study focuses on laser-induced oxidation of TC4 alloy surfaces and achieves precise color control on TC4 surfaces at room temperature using laser post-processing. The current research lacks an in-depth understanding of the mechanism responsible for color changes due to the number of processing cycles. This study aims to improve the quality of coloration through secondary processing and establish a color control mechanism based on accumulated energy density. Statistical analyses revealed notable reductions in ΔE, ΔC∗, and Δh∗, indicating enhanced color uniformity. Surface morphology and reflectance data further confirmed these findings, demonstrating the effectiveness of secondary processing in achieving consistent and uniform coloration. •Achieved consistent TC4 alloy surface colors using laser-induced oxidation, with a reproducible color palette.•Secondary processing improved ΔE by 68.9 %.•Secondary processing yielded smoother surfaces.•Similar colors were produced at comparable accumulated energy densities.