碳化硅陶瓷超快激光双光束精密抛光技术研究

Research on ultrafast laser double-beam precision polishing technology of SiC ceramics

为了有效提高碳化硅陶瓷材料抛光精度,采用了一种红外脉冲和超快紫外皮秒激光双光束抛光碳化硅陶瓷技术。通过红外纳秒激光与超快紫外皮秒激光抛光碳化硅陶瓷材料激光双光束抛光方法,实验研究了激光功率、重复频率、扫描速率、离焦量等抛光工艺参数对抛光SiC表面质量的影响。结果表明,在激光功率24 W、扫描速率200 mm/s、激光重复频率500 kHz、离焦1 mm时,陶瓷表面粗糙度达到最优,激光双光束抛光和单光束抛光原始粗糙度碳化硅2.87μm分别下降至0.42μm和0.53μm;激光双光束抛光SiC陶瓷致密化,陶瓷表面呈现有规律的整齐排列,且碳化硅抛光表面的晶粒平均大小为1.48μm,表面力学性能得到改善。该研究为陶瓷等硬脆材料激光精密抛光提供了参考。

In order to improve the polishing precision of SiC ceramics effectively,a kind of polishing technology,namely infrared nanosecond and ultrafast ultraviolet picosecond laser for silicon carbide ceramics,was designed.The effects of laser power,repetition rate,scanning rate,and defocus on SiC surface quality were investigated experimentally by using infrared nanosecond laser and ultrafast ultraviolet picosecond laser double-beam polishing mothed.The results show that the surface of the laser double-beam polished silicon carbide ceramics is compared with that of the single ultraviolet picosecond polishing ceramics,the roughness of the laser double-beam polishing and single-beam polishing decreases from 2.87μm to 0.42μm and 0.53μm respectively,with the laser power 24 W,the scanning speed is 200 mm/s,the laser repetition rate is 500 kHz,and the defocus is 1 mm.The SiC ceramics are densified by laser double-beam polishing,the ceramic surface is recrystallized and neat after polishing,and the average grain size of the SiC polished surface is 1.48μm,and the surface mechanical properties are improved.The results provide the guide for precision laser polishing of ceramics and other hard and brittle materials.