Abstract:

Helical milling operations machining process parameters planning approach were proposed based on analytical time domain cutting forces models and time and frequency domain dynamics models of the operations. The cutting forces both on the side cutting edges and on the bottom cutting edges along the helical feed path were defined by considering the circumferential feed motion and the axial feed motion of the tool. The dual periodicity which was caused by the spindle rotation, as well as the period of the helical cutting fool feed was included. Both the critical axial cutting depth and the critical radial cutting depth were solved. The cutting force model and dynamics model allowed the planning of machining process parameters including axial cutting depth, radial cutting depth, circumferential feed rate, axial feed rate and spindle rotation velocity in the chatter free zone during helical milling. Experiments were also performed in order to verify the planned machining process parameters for helical milling. No chatter occurred during the experiments. The accuracy and precision of the machined surface, including surface roughness, roundness and cylindricity, are equivalent to the boring process.

Key words: helical milling, model, dynamics, chatter, process planning

摘要：

以螺旋铣孔工艺时域解析切削力建模、时域与频域切削过程动力学建模、切削颤振及切削稳定性建模为基础,研究了螺旋铣孔的切削参数工艺规划模型和方法。切削力模型同时考虑了刀具周向进给和轴向进给，沿刀具螺旋进给方向综合了侧刃和底刃的瞬时受力特性;动力学模型中同时包含了主轴自转和螺旋进给两种周期对系统动力学特性的影响，并分别建立了轴向切削稳定域和径向切削稳定域的预测模型,求解了相关工艺条件下的切削稳定域叶瓣图。在切削力和动力学模型基础之上，研究了包括轴向切削深度、径向切削深度、主轴转速、周向进给率、轴向进给率等切削工艺参数的多目标工艺参数规划方法。最后通过试验对所规划的工艺参数进行了验证，试验过程中未出现颤振现象，表面粗糙度、圆度、圆柱度可以达到镗孔工艺的加工精度。

关键词: 螺旋铣, 模型, 动力学, 颤振, 工艺规划