激光熔覆工艺对TA1熔覆层微观组织和耐蚀性能影响

fect of Laser Cladding Process on the Microstructure and Corrosion Resistance of TA1 Cladding Laye

采用扫描电子显微镜(SEM)和强酸性溶液腐蚀试验,研究了激光熔覆工艺参数对TA1钛板表面凹坑激光熔覆层的微观组织及耐蚀性能影响。结果表明,激光功率过高或过低、扫描速度太慢或者太快,都有可能致使激光修复层微气孔、微裂纹等缺陷增加;激光功率越高,扫描速度越慢,熔覆层腐蚀越严重,与基材区的外观形貌差异越大;综合考量激光熔覆修复层的微观组织质量和耐蚀性能,采用激光功率1 800 W,扫描速度10 mm/s,光斑直径3 mm,送粉器转速2.5 r/min制备的TA1修复层组织和耐蚀性能较好。

The effects of laser cladding process parameters on the microstructure and corrosion resistance of the laser cladding layer with concave pits on the surface of TAl titanium plate were studied using scanning electron microscopy(SEM)and strong acidic solution corrosion tests.The results show that high or low laser power,slow or fast scanning speed may lead to an increase in defects such as micro pores and microcracks in the laser repair layer.Moreover,higher laser power and slower scanning speeds tend to escalate the corrosion severity of the cladding layer and magnify the morphological difference from the substrate area.To optimize the quality of the microstructure and corrosion resistance of the laser cladding repair layer,a TAl repair layer prepared with a laser power of 1800 W,scanning speed of 10 mm/s,spot diameter of 3 mm,and powder feeding rate of 2.5 r/min demonstrated favorable microstructure and corrosion resistance.