Investigation Of Mechanism In High-speed Milling Of Nickel-Based Superalloy GH706

Superalloy is widely used in the sophisticated applications due to its uniqueproperties. However, machining of such superior materials is difficult and costlydue it peculiar characteristics. The present paper based on the analysis of test andsimulation on high-speed milling of nickel-based superalloy GH706as follows.Firstly, this paper comparedthe reasons for the wear and breakagewithtwo toolmaterials, the main failure mode of cemented carbide toolis adhesion wear, thebreakagein the late is due to the joint action that accumulation of fatigue cracks andadhesive wear. The main failure form of PCBN cutting tool is brittle breakage, andoccured early in the cutting period; At the same time,this paper also studiedchipdeformation ofhigh-speed milling of nickel-base superalloy GH706. The focus ofresearch wasserrated chip and chip side flow phenomenon, while analyzed theinfluence of cutting parameters on both phenomena, and then drew a conclusionthat cutting speed has a bigger impact on both phenomena than other cuttingparameters;Meanwhile, this paper identified the cutting parameterswhich impact onthe cutting force and flank wear by ANOVA in high-speed milling of nickel-basedsuperalloy GH706, then obtained that axial depth of cut is the main factoraffectingofcutting forced, cutting speed is the main factor affecting of flank wear. Twoempirical models which based on the cutting force and flank wear were specified,and optimized the cutting parameters according to the empirical model of cuttingforce and cutting efficiency formula. Finally, this paper studied the microscopicplastic deformation of high-speed milling of nickel-based superalloy GH706byfinite element simulation method, and explainedthe reason of early breakage fromthe point of stress distribution in cutting period when used PCBN cutting tool, whilethis paper analyzed the cutting temperature, chip formation and cutting force ondifferent cutting speed and chamfer angles. The chamfer angles have a obviousinfluence on cutting force of Y direction, and chamfer angles have a bigger impact on the stress than cutting speed. This paper also illustrated the reason ofunstablethermoplasticon high-speed milling of nickel-base superalloy GH706through plastic flow, deformation rate and other related indicators.Based upon above research, this present analyzed the macroscopic phnomenonand microscopic plastic deformation of high-speed milling of nicked-basedsuperalloy for theoretical basis of manufacturing process.