Buj-Corral Irene, Ortiz-Marzo Jose-Antonio, Costa-Herrero Lluís, Vivancos-Calvet Joan, Luis-Pérez Carmelo
Universitat Politècnica de Catalunya (UPC)-Escola Tècnica Superior d'Enginyeria Industrial de Barcelona (ETSEIB), 08034 Barcelona, Spain.
Universidad Pública de Navarra-Dpto. de Ingeniería, 31006 Navarra, Spain.
Materials (Basel). 2019 Mar 14;12(6):860. doi: 10.3390/ma12060860.
In the present study, the groups of cutting conditions that minimize surface roughness and its variability are determined, in ball-end milling operations. Design of experiments is used to define experimental tests performed. Semi-cylindrical specimens are employed in order to study surfaces with different slopes. Roughness was measured at different slopes, corresponding to inclination angles of 15°, 45°, 75°, 90°, 105°, 135° and 165° for both climb and conventional milling. By means of regression analysis, second order models are obtained for average roughness and total height of profile for both climb and conventional milling. Considered variables were axial depth of cut , radial depth of cut , feed per tooth cutting speed and inclination angle . The parameter was the most significant parameter for both and in regression models. Artificial neural networks (ANN) are used to obtain models for both and as a function of the same variables. ANN models provided high correlation values. Finally, the optimal machining strategy is selected from the experimental results of both average and standard deviation of roughness. As a general trend, climb milling is recommended in descendant trajectories and conventional milling is recommended in ascendant trajectories. This study will allow the selection of appropriate cutting conditions and machining strategies in the ball-end milling process.
在本研究中，确定了在球头铣削操作中使表面粗糙度及其变化最小化的切削条件组。实验设计用于定义所进行的实验测试。采用半圆柱形试样以研究具有不同斜率的表面。在不同斜率下测量粗糙度，对应于顺铣和逆铣时15°、45°、75°、90°、105°、135°和165°的倾斜角。通过回归分析，获得了顺铣和逆铣时平均粗糙度和轮廓总高度的二阶模型。所考虑的变量有轴向切削深度、径向切削深度、每齿进给量、切削速度和倾斜角。参数在回归模型中对平均粗糙度和轮廓总高度而言都是最显著的参数。使用人工神经网络（ANN）来获得平均粗糙度和轮廓总高度作为相同变量函数的模型。ANN模型提供了高相关性值。最后，从粗糙度平均值和标准差的实验结果中选择最佳加工策略。一般趋势是，在下降轨迹中推荐顺铣，在上升轨迹中推荐逆铣。本研究将有助于在球头铣削过程中选择合适的切削条件和加工策略。
