The Experiment Of Cutting Performance Of Polished Cemented Carbide Insert In Cutting Nickel-based Superalloy

With the increasingly urgent strategic requirements of aerospace manufacturing industry of each country,nickel-based superalloy has been widely applied,but it’s easy to cause severe tool wear when machining.For its excellent comprehensive properties,the cemented carbide cutting tools are the main tools in the processing of nickel-based superalloy.So far,the main preparation of cemented carbide cutting tools are grinding,EDM,laser cladding,injection molding process and so on.But the usage of these processing methods easily lead to grinding burn,microstructure changes,micro cracks,short life and other defects which cause great damage to the cutting performance of the tool.Therefore,it has been an important research topic in the field of machining that how to effectively improve the cutting performance of a carbide insert in cutting the nickel-based superalloy.For this reason,this paper which uses a method of global planarization of Chemical Mechanical Polishing(CMP)technology can be used for fabricating the CMP pretreatment YG10 insert that can processes nickel-based superalloy with high efficiency,high quality and low cost,and determined the optimum process parameters of CMP pretreatment YG10 insert by CMP polishing mechanism,Taguchi method,variance analysis and orthogonal test theory,and studied the effects caused by the processing parameters on turning force,insert durability,insert wear,machined surface quality and chip morphology.The main research work is as follows:(1)Preparation of CMP pretreatment YG10 insert was implemented.To explore the suitable abrasive material for polishing YG10 insert by using polishing abrasives as a single factor.On this basis,the best combination of polishing process parameters has been determined,taking the material removal rate and surface roughness as the comprehensive evaluation index by using Taguchi method and variance analysis to determine.By using this parameter combination,the insert of the polished rake face is prepared.Then,the surface morphology of the insert surface after CMP pretreatment was observed by Keyence VHX-5000.(2)The comparative test of cutting force of GH4169 was implemented.The influence of processing parameters on the cutting force of two kinds of inserts in machining GH4169 was analyzed by orthogonal test and the mathematical model for the cutting force of both insert s in turning GH4169 was established.(3)The comparative test of insert durability of GH4169 was implemented.The influence of processing parameters on the durability of two kinds of inserts in machining GH4169 was analyzed by orthogonal test and the mathematical model for the durability of both inserts inturning GH4169 was established.The Keyence VHX-5000,SEM and EDS were used to observe the surface morphology of the insert and to analyze the element composition of the damaged area to reveal the wear mechanism of two kinds of inserts in turning GH4169.(4)Analysis of surface quality and chip morphology of GH4169 was implemented.The effects of processing parameters on surface roughness,degree of work hardening,chip morphology of both inserts in turning GH4169 has been analyzed,and the mathematical model of work-piece surface roughness has been established.In summary,the research in this paper not only enriches the theory preparation of cemented carbide insert and expands the processing field of cemented carbide insert,but also lays the foundation for high efficiency and low cost in processing of nickel-based superalloy GH4169.