SiC机械密封环表面微织构激光加工工艺

Processing of laser surface micro-texturing on surface of SiC mechanical seal

采用声光调Q二极管泵浦Nd:YAG激光器,利用'单脉冲同点间隔多次'激光加工工艺,对碳化硅机械密封试样端面进行激光表面微织构的加工工艺试验研究.采用Wyko-NT1100表面形貌三维测量仪测量了微织构的几何形貌参数,分析了泵浦电流、脉冲重复频率、脉冲重复次数和扫描速度等激光加工工艺参数对微凹腔和微凹槽织构的几何形貌参数与加工质量的影响.结果表明,泵浦电流和脉冲重复次数对微凹腔的几何形貌参数与加工质量影响较大,而重复频率的影响则相对较小;泵浦电流、扫描速度和重复频率对微凹槽的加工质量均有较大影响.通过优化激光加工工艺参数组合,可以加工出较优的微观几何形貌.加工微凹腔较优的工艺参数范围:泵浦电流为14～16 A,脉冲重复次数为1～10次;加工微凹槽的较优工艺参数范围:泵浦电流为14～16 A,重复频率为1 500～2 500 Hz,扫描速度为8～25 mm/s.

The laser surface texturing on the SiC mechanical seal samples were studied by using a Q-switched diode-pumped Nd：YAG laser and the laser processing technique called ＂single pulse at a time, repeated at intervals＂, and the geometric parameters of texture were measured by means of Wyko-NT1100 surface profiler, further the effect of laser processing parameters （ pumping current, repetition frequency, number of excitations, scanning speed） on the geometrical parameters and quality of micro-textures was analyzed. The results show that pumping current and number of excitations have an evident influence on the micro-pore processing quality, and repetition frequency is relatively small. However,pumping current, scanning speed and repetition frequency can greatly affect micro-groove processing quality. High quality micro-textures can be obtained via optimizing the laser processing pa- rameters. For processing micro-dimple, the optimal laser parameters, such as pumping current and number of excitations are 14 - 16 A, 1 - 10, for processing micro-groove. However, the optimal pumping current, repetition frequency and scanning speed are 14 -16 A, 1 500 -2 500 Hz and 8 -25 ram/s, respectively.