磨粒流抛光粗糙度预测模型研究

Study on Prediction of Surface Roughness for Abrasive Flow Machining

磨粒流抛光是实现整体叶盘等复杂结构零件内表面抛光的有效手段,实现抛光表面粗糙度可控可预测是磨粒流加工研究中的重要问题。以简单高长径比管件为研究对象,研究磨料介质在工件表面的动力学特性,提出基于磨粒流抛光的表面粗糙度预测模型,并实验验证了模型的有效性。此基础上,开展整体叶轮叶片复杂型面的磨粒流抛光实验,并将实验结果与数值模拟进行对比。结果表明:磨粒流抛光方法可应用于整体叶轮叶片复杂型面的光整抛光,工件表面粗糙度从初始的S_(a) 0.76µm降低至S_(a) 0.30µm,表面粗糙度改善程度达60%。实验结果与数值模拟之间的误差为19.5%±4.9%,实现了叶轮叶片的光整抛光和表面粗糙度预测。

Abrasive flow machining is an effective method to polish the inner surface of complex structural parts,e.g.,impeller and blade.The implementation of controllable and predictable surface roughness is an important issue in the field of abrasive flow finishing.With the straight pipes with high aspect ratio selected as the workpieces,the dynamic characteristics of the abrasive media are studied in surface finishing process,and a surface roughness prediction model is proposed.Corresponding experiments are performed to validate the model.On the basis,experiments on impeller are carried further and results are compared with the established model.The results of experiments show that AFM can be used in polishing blades of impeller.After AFM process,the surface roughness decreases form S_(a) 0.76μm to S_(a) 0.30μm with improvement of 60%.The error with value of 19.50%±4.94%between experiments and surface roughness model show its effectiveness and validation in anticipation of surface roughness of complex parts.