Li Xinyan, Wang Dan, Gao Juming, Zhang Weiwei, Li Canyang, Wang Nianzheng, Lei Yucheng
School of Materials Science and Engineering, Jiangsu University, Zhenjiang 212013, China.
Key Laboratory of High-end Structural Materials of Jiangsu Province, Jiangsu University, Zhenjiang 212013, China.
Materials (Basel). 2020 Nov 26;13(23):5363. doi: 10.3390/ma13235363.
The removal of the surface paint of Q345 (Gr·B) steel, as well as microstructure and hardness of the cleaned surface were investigated. The laser source used in this study is a nanosecond pulsed Gaussian light source. The surface morphology and microstructure were characterized by a scanning electron microscope and electron back-scattered diffraction. A hardness test was used for capturing variations of the parameter of the cleaned region in comparison to the base metal. The results show that when the X-scanning speed was 1500 mm/s and Y-moving speeds was 7 mm/s during ns-laser cleaning, respectively, the cleaned surface was relatively flat and there was only a few small residual paint. In addition, the contents of Fe and C elements on the cleaned surface reached to 89% and 9%, respectively. Moreover, the roughness was the lowest of 0.5 μm through the observation of the three-dimensional topography. In addition, a fine grain layer appeared on the cleaned surface after laser cleaning at the X-scanning speeds of 500 mm/s and 1000 mm/s. The maximum hardness of the fine grain layer was more than 400 HV, higher than the base metal.
对Q345（Gr·B）钢表面涂层的去除情况以及清洁后表面的微观结构和硬度进行了研究。本研究中使用的激光源是纳秒脉冲高斯光源。通过扫描电子显微镜和电子背散射衍射对表面形貌和微观结构进行了表征。采用硬度测试来获取清洁区域与母材相比参数的变化情况。结果表明，在纳秒激光清洗过程中，当X扫描速度为1500 mm/s且Y移动速度为7 mm/s时，清洁后的表面相对平整，仅有少量残留漆。此外，清洁表面上Fe和C元素的含量分别达到了89%和9%。而且，通过三维形貌观察，粗糙度最低为0.5μm。另外，在X扫描速度为500 mm/s和1000 mm/s进行激光清洗后，清洁表面出现了细晶层。细晶层的最大硬度超过400 HV，高于母材。
