Study On Surface Integrity Of Nickel-based Superalloy By PCBN Cutting Tool

Nickel-based superalloy has excellent high-temperature mechanical properties and is widely used in aerospace,nuclear submarine,petrochemical industry and so on.But nickel-based superalloy is typical difficult-to-machine materials,the tool wear is serious and the surface processing quality is poor in the process.With the rapid development of aerospace,higher requirements on the surface quality and processing efficiency of nickel-based superalloy are put forward,the surface integrity of nickel-based superalloy by PCBN has been becoming the focus research in recent years.Firstly,the experiment of PCBN cutting tool turning nickel-based superalloy is done by schemes of single factor and orthogonal test,metallographic samples of nickel-based superalloy are prepared.The influence of different cutting parameters on the microstructure and surface defects of machined surface is analyzed,effect of microstructure change on material properties is studied,existing form and formation mechanism of surface defects are discussed.Secondly,according to the test data measured by cutting experiment,the effect of different cutting parameters on surface roughness is discussed,influence of cutting parameters on surface roughness is discussed by Range analysis method.Surface hardening test of nickel-based superalloy is done,the effects of different cutting parameters on hardening depth and hardening degree are studied.Thirdly,the machined surface of residual stress was tested by X-ray method,the effect of different cutting parameters on the machined surface of residual stress was analyzed.The mechanism of residual stress variation of the machined surface is explored.Finally,fuzzy comprehensive evaluation system was used to evaluate the surface quality evaluation index of nickel-based superalloy,optimum cutting quality when surface machining quality is best,it provides theoretical basis and technicalreference for studying the surface quality of nickel-based superalloy.