航空发动机叶片精密自适应砂带磨削技术及试验研究

Self-Adaptive Belt Grinding Technology and Its Experimental Research on Aero-Engine Blade

叶片的型面精度和表面完整性直接制约着航空发动机的工作性能及使用寿命。由于叶片具有薄壁易变形、材料难加工及砂带磨削柔性接触等特征而难以实现精密磨削,由此提出了一种基于检测—加工一体化的自适应砂带磨削加工方法。首先根据叶片结构特点,设计了边缘磨削工位磨头和圆角磨削工位磨头,分别用于磨削叶片型面及进排气边缘、阻尼台及根部转角等部位;其次基于模型重构的几何误差进行了自适应软件的研制;最后通过双工位集成的七轴联动数控砂带磨削中心进行了叶片磨削试验。试验结果表明,磨削后的叶片表面粗糙度Ra≤0.4μm,加工误差保持在±0.05mm范围内,叶片型面磨削加工周期仅为3.5h,满足叶片加工要求。因此,自适应砂带磨削技术是实现叶片精密磨削加工的有效技术手段。

The profile accuracy and surface integrity of blades directly restrict the performance and service life of the aero-engine.Because of the characteristics of thin-wall deformation and difficult material processing and flexible contact,it is difficult to achieve a precision grinding.Therefore,a self-adaptive abrasive belt grinding method based on the integration of defection and machining was proposed.Firstly,according to the characteristics of the blade structure,the edge grinding and round angle grinding devices were designed,which were used to grinding the blade surface and LTE(the leading and the trailing edges),the damping table and the root corner.Secondly,self-adaptive software was developed based on geometric error of model reconstruction.Finally,the blade grinding test was carried out through the double position integrated seven axis CNC grinding center.The results show that the surface roughness of the blade is less than 0.4μm,the machining error is kept within the range of 0.05mm,and the grinding period is only 3.5h,which satisfies the processing requirements of the blade.Therefore,the self-adaptive abrasive belt grinding technology is an effective method for precision grinding of blades.