The simulation and process optimization for laser marking of submillimetre rasterizing 2D code on stainless steel are investigated. For 50CrVA stainless steel, the temperature field of material during laser marking is obtained by numerical modeling. The results show that temperature change in the depth direction and oxidation degree of laser radiation region are the fundamental reasons for the contrast of 2D code, but the temperature change occurs in the radius direction for the print growth. The threshold of laser average power and [Formula: see text] frequency for an identifiable submillimetre 2D code are, respectively, 3.0 W and 100 KHz, which matches the simulation well within normal operating conditions. It is also found that an increase of the pulses number effectively improves the contrast and the appearance consistency of modules in DM code. Besides, corrosion tests show that the corrosion resistance of submillimetre 2D code is greatly improved by covering a layer of transparent polyurethane coating. Finally, a sample of submillimetre 2D code marked on cylindrical tool with diameter of 1 mm is obtained. In conclusion, the method could obtain submillimetre code with high reading quality and corrosion resistance by minimizing the characteristic edge over-burn effects, which provides theoretical basis and experimental method for identification of small parts.

中文翻译：

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不锈钢亚毫米光栅二维码激光打标仿真与工艺优化

研究了不锈钢亚毫米光栅二维码激光打标的仿真与工艺优化。对于50CrVA不锈钢，激光打标过程中材料的温度场是通过数值模拟得到的。结果表明，深度方向的温度变化和激光辐射区域的氧化程度是造成二维码对比度差异的根本原因，而径向温度变化则发生在打印生长的半径方向。可识别的亚毫米二维码的激光平均功率阈值和 [公式：见文本] 频率分别为 3.0 W 和 100 KHz，这与正常操作条件下的模拟非常匹配。还发现脉冲数的增加有效地提高了DM代码中模块的对比度和外观一致性。此外，腐蚀测试表明，通过覆盖一层透明聚氨酯涂层，亚毫米二维码的耐腐蚀性能大大提高。最后，获得了标记在直径为 1 mm 的圆柱形工具上的亚毫米二维码样本。综上所述，该方法可以通过最大限度地减少特征边缘过烧效应，获得具有高读取质量和耐腐蚀性的亚毫米码，为小零件的识别提供理论依据和实验方法。获得了标记在直径为 1 mm 的圆柱形工具上的亚毫米二维码样本。综上所述，该方法可以通过最大限度地减少特征边缘过烧效应，获得具有高读取质量和耐腐蚀性的亚毫米码，为小零件的识别提供理论依据和实验方法。获得了标记在直径为 1 mm 的圆柱形工具上的亚毫米二维码样本。综上所述，该方法可以通过最大限度地减少特征边缘过烧效应，获得具有高读取质量和耐腐蚀性的亚毫米码，为小零件的识别提供理论依据和实验方法。