Research Of Using Laser Direct Marking Two-Dimensional Barcode Technology On45Steel

Laser direct marking is playing a dominate role among all Direct Part Marking techniques to produce graphics or characters. Laser direct marking and bar code technology, as well as Automatic target recognition technology, are combined in our work. Data Matrix codes are marked on both planar and cylindrical45steel by the use of direct laser marking technology. Considering the process performance and durability of the mark symbols, study is carried out on the sets of laser parameters, the assessment of the marks and the symbols’reliability under tough environment. And the detailed work is showed as follows:At first, choose a10×10mm2DM symbol delivering "ABCDEFG" as object symbol, use laser etching method to conduct marks on45steel. YAG-T80C laser making machine works as marking equipment and DVT machine vision system developed by COGNEX is employed as identifying tool. After that design single variable control experiment and study the effect trend of processing parameters, including Q frequency f (KHz), the laser current I(A) and laser marking speed v (mm/s), on the bar code quality. According to ISO/IEC16022, decoding grade, symbol contrast, print growth, axial nonuniformity and unused error are all gathered to be evaluating norms to construct a quality evaluating system, which can contribute to the optimization of the process parameters.After the optimization of the sets of parameters, do the same sets and operate marking on the cylindrical steel. Choose successful/fail reader and time cost during identifying as index to evaluate symbol marked, analyze the interrelation between size of DM symbol and diameter of the cylindrical steel and detect the distortion of the symbol caused by the curve of the surface. Considering high-intensity specular reflection light existing in cylindrical steel, study about how to improve the identification of DM symbol on curve surface is also referred, besides this the setting of light exposure in the software concerned, the layout of light,the contrary symbol marking technology and image preprocessing are also researched in detail.Thanks to the Probability theory and Mathematical statistics, the study about durability of DM symbol is achieved. By conducting a series of simulating experiment on parts with treatment of wearing, oil, rust and scratch, we conclude that parts with anti-rust oil applied placed in sealing environment will greatly improve their durability.Conclusion from this paper has vast importance to applying laser marking technology on45steel and there is no doubt that it will join the procession as a guide to instruct production in industry.