大深宽比钛合金整体构件高效加工技术研究

Research on High Efficiency Machining of Titanium Alloy Integral Structural Parts With Large Depth-Width Ratio

飞机大深宽比钛合金整体构件的工艺规划和高效精准加工是先进战机重要零件制造的一大瓶颈。在分析整体翼肋材料特性、结构特征、加工难点的基础上,制定了基于三轴机床和五轴机床协同制造的总体高效加工工艺路线,规划了基于变刚度特性的装夹点。针对小曲率区域特征,提出了定夹角大步距铣削方法;针对深腔加工颤振、切削效率低的问题,提出了刚性稳态分层加工方法;针对精准的重量要求,提出了拓角度闭角无残留精准加工方法。最后,应用上述方法,高效地加工出合格零件,为批量生产提供技术支撑。

In the context of the manufacturing process of some essential parts of advanced fighter aircraft,the task of process planning,as well as the concern of efficient and accurate machining for titanium alloy integral structural parts with large depth-width ratio,acts as a major bottleneck.In this paper,based on the analysis of the material characteristics and structure features of the integral wing rib,coupled with the analysis of its corresponding machining difficulties,the overall efficient machining process route is firstly formulated,which entails the collaborative manufacturing of three-axis machine tool and five-axis machine tool.The clamping points are thus determined by considering the characteristic of variable stiffness.On account of the characteristic of small curvature of the cutting area,the machining strategy with the conditions of constant angle and large side-step upheld is adopted.Aiming at the existing problems of chatter of the deep cavity machining and low efficiency,a rigidity and stability oriented layered milling method is thereby proposed.With the demand of precise weight,an additional angle assisted precision machining method for narrow angle without uncut material is then presented.Finally,the parts quality and machining efficiency are guaranteed by adopting the aforementioned methods,thus providing technical support for the mass production.