Mechanics-based feedrate scheduling for multi-axis plunge milling

Abstract

Multi-axis plunge milling has an increasing application in the manufacturing industry to rough machine complex parts, such as blisks and impellers. In order to prevent excessive cutting forces and unexpected tool breakage, cutting parameters of multi-axis plunge milling are usually assigned to be conservative according to the maximum cutting load in one feeding phase. This is an obstacle to improve the productivity of rough machining. To address this challenge, an original approach is proposed to schedule the feedrate of multi-axis plunge milling based on the mechanistic model. The cross section of the removed material is used to calculate the complicated engagement of multi-axis plunge milling. First, an accurate mathematic model of the cross section is established by its defining parameters. Second, a specific mechanistic model for multi-axis plunge milling is deduced based on the identified cross section. Then, a mechanics-based feedrate scheduling strategy is proposed to regulate the cutting forces and torque in multi-axis plunge milling. Finally, three feedrate scheduling methods with different references are conducted and compared in experimental tests to verify this new approach. The method proposed in this paper can reduce the cutting time and smooth the variances of cutting forces and torque.