激光精细表面制造工艺研究及应用:清洗与抛光

Research and Application of Laser Fine Surface Processing Technology:Cleaning and Polishing

介绍了激光精细表面制造中的两类关键技术——激光清洗和激光抛光,以及其在提高结构材料表面质量和性能表现中的研究和应用。采用激光清洗技术去除铝合金表面氧化层,清洗表面氧含量显著降低,从而明显提高铝合金焊缝质量,避免熔合区气孔形成;通过激光抛光技术对增材成形钛合金构件进行抛光,可将表面粗糙度由5μm以上降低到1μm以下,同时激光抛光钛合金表面发生相变,使表面硬度和耐磨性得到显著提高。最后,进一步讨论激光清洗和抛光复合技术处理Ni-Ti形状记忆合金(SMA)表面的可行性。

In current work, two key techniques in laser fine surface processing--laser cleaning and laser polishing--are introduced in the improvement of material surface quality and performance. On the one hand, laser cleaning technique was used to remove the oxide layer on commercial aluminum alloy （5A06） surface. Results reveal that oxygen content on the laser treated surface is significantly decreased, improving the welding quality and avoiding the formation of porosity in fusion zone. On the other hand, laser polishing process is carried out on the laser-based additive manufactured titanium alloys （TC4 and TCll）, showing that as-received Ti-based alloys with surface roughness more than 5μm can be reduced to less than 1μm through laser polishing process. Meanwhile, phase transformation occurs on the laser polished Ti-alloy surfaces, which brings great enhancement of microhardness and wear resistance. Finally, it was furtherly discussed on the composite laser treatment on Ni-Ti shape memory alloy （SMA） surface by combining laser cleaning and polishing tech- nologies.