Parametric chip thickness model based cutting forces estimation considering cutter runout of five-axis general end milling

Abstract

In the process of sculpture surfaces machining, due to the changes of the cutter orientation and the inevitable eccentricity between tool and spindle, machining parameters optimization based on five-axis cutting force is quite a challenge. To solve this problem, this study proposes a new method, cutting edge element moving(CEEM) method, to calculate instantaneous undeformed chip thickness(IUCT), to distinguish cutter/workpiece engagement(CWE) area and to simulate five-axis machining cutting force considering runout for general end mills. On the basis of upper work, the parameter representation of IUCT is deduced by the parametric expression of coordinate transformation matrix and feed vector, and resolved to three sub models about tool orientation, tool orientation change and cutter runout. At last, cutting force coefficients and cutter runout parameters are calibrated by cutting test and dial gauge testing. And inclined axis cutting test for bull nose mill, cylinder face-milling test for ball end mill and conical surface flank milling test for flat end mill are carried out to verify the effectiveness of the proposed model and related decomposition model. Combined with the specific test, some analysis about peak values, mean values and peak to peak difference values of cutting forces in various tool orientations are conducted, and the effect to cutting force from the changes of lead and tilt angles are evaluated. Some conclusions obtained and the methods utilized can be used to optimize tool orientation and feed rate etc.