整体闭式叶轮五轴侧铣刀具的适配性设计基础研究

Integral enclosed impeller is a kind of new high performance impeller which is mainly used for the engines in aerospace industry. Integral enclosed impeller has several characteristics such as integral and enclosed in the structure, blade with sculptured surfaces of high dimension geometry, made of difficult-to-cut material, thin wall, as well as low machining damage requirement. Five-axis flank milling and special cutting tool based on multi-axis control NC machining and linear contact between cutting edge and workpiece are key manufacturing technologies for the high efficiency, high accuracy and high surface integrity machining of integral enclosed impeller. this project deals with the fundamental research on adaptive design for cutter used in five-axis flank milling in which can be described as characterization of cutter and workpiece engagement, cutter accessibility analysis, milling stability analysis and chatter suppression. From certifying the differential geometry of cutter-workpiece engagement surface and its dynamic evolution mechanism, establishing the mapping relationship between cutter parameter, cutter posture and accessibility considering multi constraints, as well as analyzing the dynamic interaction mechanism between cutter and flank milling process, the stability behavior of variable pitch and helix tool will be discussed. As a result, the adaptive design principle, method and rule for the cutter used in five-axis flank milling will be presented, and the result can be act as theoretical instruction and experimental support for the integrated, precisely and digital design for cutter's shape, parameter and dynamic behavior.

整体闭式叶轮是一种结构整体成型、型腔封闭狭小、型面复杂异构、型面精度苛刻、材料难于切削、薄壁易于变形、极低损伤要求的新型高性能叶轮，基于多轴数控加工和刀具侧刃线接触的五轴侧铣工艺和专用刀具是实现此类零件高效率、高精度、高表面完整性加工的关键技术。（1）本项目从刀具-工件接触表面状态表征、刀具空间可达性分析、刀具铣削稳定性分析和颤振抑制三个方面开展五轴铣削刀具适配性设计的基础研究；（2）拟从理论上阐明刀具-工件接触表面的微分几何特性及其动态演变机制，多重约束条件下的刀具特征参数、姿态与空间可达性的映射关系，刀具-侧铣加工过程的动态交互机理与变导程刀具侧铣加工的稳定性行为等影响刀具结构、参数和动态特性设计的关键科学问题；（3）将提出一种适用于整体闭式叶轮五轴侧铣刀具适配性设计的原理、方法和准则，为实现刀具结构、参数和动态特性的一体化、精确化和数字化设计提供理论基础和试验依据。

整体闭式叶轮是一种结构整体成型、型腔封闭狭小、型面复杂异构、型面精度苛刻、材料难于切削、薄壁易于变形、极低损伤要求的新型高性能叶轮，基于多轴数控加工和刀具侧刃线接触的五轴侧铣工艺和专用刀具是实现此类零件高效率、高精度、高表面完整性加工的关键技术。本项目从刀具-工件接触表面状态表征、刀具空间可达性分析、刀具铣削稳定性分析和颤振抑制三个方面开展五轴铣削刀具适配性设计的基础研究；从理论上阐明了刀具-工件接触表面的微分几何特性及其动态演变机制，多重约束条件下的刀具特征参数、姿态与空间可达性的映射关系，刀具-侧铣加工过程的动态交互机理与变导程刀具侧铣加工的稳定性行为等影响刀具结构、参数和动态特性设计的关键科学问题；提出了一种适用于整体闭式叶轮五轴侧铣刀具适配性设计的原理、方法和准则，为实现刀具结构、参数和动态特性的一体化、精确化和数字化设计提供了系统的理论基础和试验依据。项目针对铣刀侧刃与工件表面形成有效的高阶线接触和刀轴方向变化显著的特点，通过阐明刀具－工件接触表面的微分几何特性及其动态演变机制，为刀具轮廓形状精准设计、切削力精确预测和阈值控制提供几何学依据。针对封闭加工区域对于刀具及其包络运动的空间可达性要求，以及较大直径和包络体积的刀具在整体强度、切削稳定性、材料去除率方面的优势，通过阐明多重约束条件下刀具特征参数、姿态与空间可达性的映射关系，建立任意刀位点的刀具可达性范围，为刀具体积最大化设计提供依据。针对整体闭式叶轮五轴侧铣加工过程易于发生铣削颤振和一系列不良加工效应的问题，通过揭示刀具－侧铣加工过程的动态交互机理与变导程、变螺旋角刀具侧铣加工的稳定性行为，有助于以离线方式抑制铣削颤振。