干气密封端面型槽可控激光制备的参数模型及实验验证

Parameter Model and Experimental Verification of Controllable Laser Preparation of Dry Gas Seal Surface Groove

针对干气密封微米级开槽深度和粗糙度控制难的问题,提出相应评价方法,建立加工深度和粗糙度模型,并通过数值模拟系统地研究了激光填充间距S、光斑直径ds与开槽深度ha、粗糙度Ras之间的关系.结果表明:开槽深度和粗糙度均随填充间距的增大而减小,当填充间距S<7μm时填充间距对槽深和粗糙度的影响十分显著;光斑直径对开槽深度的影响基本可以忽略,粗糙度随光斑直径的增大呈先缓慢增大后迅速升高的趋势,临界值也位于ds=7μm左右.实验结果对数值计算中槽深的分析结果支持度较好,与粗糙度的分析结果略有出入.进一步采用TOPSIS综合评价方法优选出最佳工艺参数范围:考虑加工效率时,最佳参数区间为8μm≤S≤15μm,9μm≤d_(s)≤15μm;不考虑加工效率时,最佳参数区间为5μm≤S≤10μm,5μm≤d_(s)≤15μm.研究结果对进一步提高干气密封微米级槽深的加工效率、精密度有一定指导意义.

To address the difficulty in controlling groove depth and roughness during micron-level groove machining of dry gas seals,a theoretical evaluation method was proposed,and a model was constructed to investigate the machining depth and roughness.Using this numerical simulation,the relationships between the laser fill spacing S and spot diameter ds,and the resulting groove depth ha and roughness Ras were systematically investigated.The results demonstrate that the groove depth and roughness decrease with the increasing filling spacing,and the influence on groove depth and roughness is significant when S 7 μm.The effect of spot diameter on the groove depth is insignificant,the roughness initially increased slowly and then rapidly with the increase in spot diameter,and the critical value of ds was approximately 7 μm.The experimental results well supported those of the numerical analysis of groove depth,which was slightly different from the results of roughness analysis.In this study,the TOPSIS comprehensive evaluation method was used to optimize the optimal range of the processing parameters:considering the processing efficiency,the optimal parameter ranges are 8 μm ≤ S ≤ 15 μm and 9 μm ≤ds ≤ 15 μm;however,when the processing efficiency is not considered,the optimal parameter ranges are 5 μm ≤S ≤ 10 μm and 5 μm ≤ d_(s) ≤ 15 μm.The research results have certain guiding significance for further improving the high efficiency and precision machining of micron-level groove depth of dry gas seal.