Experimental Investigation Of Dry Cutting Of Inconel718 And Discrete Element Method Simulation Of Ceramics-tool Wear

Owing to its properties such as high oxidation resistance, corrosion resistance and mechanical strength at 650℃or higher temperatures, nickel-based super alloys are widely used in as aircraft engine parts etc . But due to its lower thermal conductivity, work hardening, presence of abrasive carbide particles, it is classified as"difficult-to-cut materials". In machining process, a major limitation of the tool life is due to friction that occur at the tool–chip interface, Tool wear influences the surface quality and dimensional accuracy of the finished product. Tool Wear under extreme mechanical and thermal loading, It is very hard to analysis physico-chemical phenomena at the tool-chip interface using only experimental means since the contact between the tool and the machined material occurs under extreme mechanical and thermal loading. The flow of the chip results in removing from particles of the tool and/or the surface at the tool-chip interface, these particles are considered the third body, which generates different wear mechanisms. By using experiments and discrete element method, a comprehensive study is carried out on the cutting process of Inconel718,morphology on machined surface and tool wear. The work in the thesis can provide a new way to analyse the tool wear.The whole thesis was divided into four chapters, and the contents of each chapter were briefly described as follows.In chapter 1, the backgrounds and significances of this research is introduction first. Then, the state of the art in the research of machining characteristic and tool-wear are summarized. And the research contents and the overall framework of this thesis were also proposed.In chapter 2, experiment on dry cutting of Inconel718 was carried out, the physical quantities such as cutting force was researched, and cutting speed and cutting depth were also qualitative analyzed; after that,machined surface morphology, such as surface roughness, surface hardening layer, surface topography and chip were researched; at last, the tool morphology was also discussed and tribological parameters were calculated.In chapter 3, considering the three aspects influences such as cutting thermal,corrosion and viscosity, modeling of the tool-chip contact was constructed with the PFC2D software. In chapter 4, DEM simulation of tool-wear basing on the established Bonded Particle Model was carried out, cutting speed and cutting depth were also qualitative analyzed and compared with the experiment results.Finally, the whole work in this thesis was systematically summarized, and the outlook for further study was discussed.