在自主研发的微小型车铣中心上,采用正交可旋转中心复合设计的二次响应曲面法对硬铝合金进行了微细铣削试验,分析了铣削参数(切削速度、每齿进给量、切削深度)对表面粗糙度的影响。基于二阶响应曲面法建立了表面粗糙度预测模型,根据试验结果,采用最小二乘估计得出回归系数,对回归方程进行了显著性检验,并对切削参数影响表面粗糙度的线性效应、二次效应和交互效应的显著性进行了比较。结果表明:在一定工艺参数范围内,切削速度对微细铣削表面粗糙度的影响最大,每齿进给量次之,切削深度影响最小;二次响应曲面法预测模型回归显著,置信度高,可以用于进行加工前的切削参数选择,以达到对表面粗糙度进行预测和控制的目的。
The influence of parameters used in micro--milling process on roughness of aluminum surface machined by a micro turn--milling NC machine developed by authors was analyzed based on RSM. The cutting parameters included cutting speed, feed per tooth, and depth of cut in the orthogonal design experiments central composite. A predictive model for surface roughness in micro-- milling was established by RSM and the significances of the regression equation and regression factor coefficients were proved herein. It appears that the cutting speed has a significant effect on surface roughness and the next one is feed per tooth, the depth of cut has a little effect under the current experimental conditions. Analysis of variance was performed to evaluate the significance of regression. The fitting degree of the model is high. The parameters used in micro--milling can be selected to improve the quality of the surface based on the model of the paper.