摘要
探求切削力、振动和表面粗糙度之间的相互关系,对实现表面粗糙度的预测预报具有重要意义。以MQL铣削45钢为试验对象,进行了切削速度v、每齿进给量f_z、切削深度a_p的三因素四水平的64组切削试验,在线测量主切削力、轴向力和径向力及振动,对切削分力数据处理得到相应的平均值、标准差和均方根值,同时离线测量出二维粗糙度R_a、三维粗糙度平均值S_a和均方根值S_q。采用正态分布、指数分布、Gamma分布、Weibull分布和Cauchy分布等函数拟合,根据AIC准则确定出最优分布函数,采用极大似然法估计出未知参数。使用Gaussian Copula、t-Copula、Frank Copula、Gumbel Copula、Clayton Copula等Copula函数拟合铣削力、振动和粗糙度之间相关结构形式,采用AIC准则优选出最优Copula函数,并确定出参量。利用最优Copula函数导出的Kendall秩相关系数τ作为评价指标,分析比较了铣削力、振动与表面粗糙度的整体相关性。采用混合Copula函数对铣削力、振动与表面粗糙度的尾部相关性进行了分析。
To explore the relationship between cutting force, vibration and surface roughness is of great significance to predict surface roughness. In this paper, the 64 all-factor experiments of milling 45 steel were conducted with the control variable method of three factors and four levels of cutting speed v, feed per tooth fz and cutting depth ap. The main cutting force, axial force, radial force and vibration were measured on line, and the corresponding average value, standard deviation and RMS values of cutting force were obtained. At the same time, the two-dimensional surface roughness Ra, three-dimensional roughness average Sa and RMS Sq were measured off-line. Then five distribution functions such as Normal distribution, Exponential distribution, Gamma distribution, Weibull distribution and Cauchy distribution were used to fit the sample data. The optimal distribution function was determined by AIC criteria, and the unknown parameters were estimated by maximum likelihood method. The five Copula functions such as Gaussian Copula, t-Copula, Frank Copula, Gumbel Copula, and Clayton Copula were used to fit the related structural forms between milling force, vibration, and roughness, and the optimal Copula function was selected according to the AIC criteria and the parameters are determined. Deriving from the optimal Copula function, the Kendall rank correlation coefficient τ was chosen as the evaluation index to analyze and compared the overall relativity between milling force and surface roughness. A mixed Copula function was constructed to analyze the tail correlation between milling force and surface roughness.
作者
裴宏杰
陈钰荧
李公安
刘成石
王贵成
PEI Hongjie;CHEN Yuying;LI Gongan;LIU Chengshi;WANG Guicheng(School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China)
出处
《航空制造技术》
2019年第9期59-67,共9页
Aeronautical Manufacturing Technology
基金
国家科技重大专项资助项目(2013ZX04009031–4)
江苏省普通高校研究生科研创新计划(CXZZ12–0658)
关键词
COPULA函数
铣削力
振动
表面粗糙度
精密加工
相关性
微量润滑
Copula function
Milling force
Vibration
Surface roughness
Precision machining
Relevance
Minimum quantity lubrication
