微小整体叶轮作为微型发动机的重要组成部分,其加工质量直接影响微型发动机的使用性能。针对微小整体式复杂叶轮流道狭窄、叶片扭曲大和长厚比大等特点,开展了微小复杂扭曲整体式叶轮五轴联动微细铣削加工方法研究。针对微小叶轮加工过程极易发生变形、过切和碰撞干涉等问题,对微小叶轮的加工过程进行工艺规划,建立了微小叶轮流道加工刀具选择的约束方程,计算出叶轮加工刀具的最大理论直径。通过CAM软件对叶轮进行切削仿真,验证了刀具选择和工艺规划的正确性。通过五轴联动微细铣削试验,得到了具有6个直径10mm的叶片、叶片最小厚度0.15mm、叶片最小相邻间距0.58mm的7075铝合金微小整体叶轮。
As the key component of the micro engine,the machining quality of the micro integral impeller has a direct effect on the performance of the micro engine. In view of the micro integral impeller characteristics of narrow flow channel,large blade twist and long thick ratio of blade,a five axis micro milling method for machining micro complex and twisted integral impeller is studied. Aiming at the problems of deformation,over cutting and collision interference in the process of micro impeller machining,the machining process of micro impeller is planned. The constraint equation of the tool diameter selection for channel cutting is established,and the maximum theoretical tool diameter is calculated. The cutting process of the impeller is simulated by CAM software,thus,the correctness of tool selection and process planning is verified. Through five-axis micro milling experiment,a high quality 7075 aluminum alloy impeller with diameter of 10 mm,6 blades,0.15 mm minimum blade thickness,and 0.58 mm minimum distance between the adjacent blades is obtained.