Laser-induced colour marking—Sensitivity scaling for a stainless steel

• Published in: Applied surface science Vol. 264; pp. 229 - 236
• Main Authors: Antończak, Arkadiusz J., Kocoń, Dariusz, Nowak, Maciej, Kozioł, Paweł, Abramski, Krzysztof M.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01-01-2013; Elsevier
• Subjects: CIE Lab; Colorimetric; Colour; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Fibre laser; Laser colour marking; Physics; Stainless steel; Surface oxidation; 42.62.Cf; CIE Lab; Surface oxidation; Stainless steel; 81.65.−b (81.65.Mq); 07.60.Dq; Laser colour marking; 42.55.Wd; Fibre laser; Colorimetric; Colour; a; b; Physical radiation effects; Stainless steels; Fibers; Laser radiation; 81.65.―b(81.65.Mq); Scaling laws; CIE L; Oxidation
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2012.09.178

► Effect of parameters of laser colour marking on the colour obtained were analyzed. ► The investigations were performed for AISI 304 stainless steel using a fibre laser. ► For all those parameters which affect the colour, stability of 10−2 (1%) is required. ► Modifications to achieve greater repeatability of colour marking were proposed. ► Two types of ageing tests, UV radiation and a salt spray test, were performed.
This paper presents the results of measurements and analysis of the influence of laser marking process parameters on the colour obtained. The study was conducted for AISI 304 multipurpose stainless steel using a commercially available industrial fibre laser. It was determined how various process parameters, such as laser power, pulse repetition rate, scan speed of the material, spacing between successive lines, thickness and temperature of the material, location of the sample relative to the focal plane, size of marked fields and position in the workpiece, affect the repeatability of the colours obtained. For objective assessment of colour changes, an optical spectrometer and the CIE colour difference parameter ΔEab* were used. Additionally, in order to determine the susceptibility of laser colour marking to the ageing process, two types of tests – UV radiation and a salt spray test – were performed. Based on this analysis, necessary modifications to the laser systems commonly used for monochrome marking are proposed in order to achieve greater repeatability in colour marking.