Surface Roughness And Tool Wear In High-speed Turning Inconel718with Ceramic Tools

Currently, Nickel-based superalloys play an increasingly important role in the field of aerospace industry and Inconel718is the most widely used alloy in Nickel-based superalloys. Due to its prominent performance, Inconel718is widely used in high-temperature field including casing,gasturbines, firebox, spacecraft, nuclear reactors, etc. However, Inconel718belongs to difficult-to-cut materials due to its high cutting force, high cutting temperature,severe work-hardening and rapid tool wear in the cutting process. How to improve the efficiency of maching and extend the life of cutter is always the problem which needs to be urgently solved and promotes our aerospace literature and art.It cannot meet the modern production application as the extremely low efficiency and poor surface quality to machine Nickel-based superalloy Inconel718with conventional cutting speed. With the appearance of high rigidity numerical control machine tools and high-performance cutting tools materials,the application study of high-speed machine has been paid to more and more great attention. High-speed machining can not only dramatically improve the efficiency but also, what’s more important, obtain high surface quality of the product with high assembling accuracy. So there is important academic significance and application value to carry out high speed cutting Inconel718to improve the efficiency and surface quality. In view of the foregoing, the research of this paper is divided into the flowing parts:(1) In this research, in high speed turning of Inconel718, orthogonal experiments were conducted to investigate the effect of cutting parameters on the surface roughness and tool wear with Sialon ceramic tool and SiCw-Al2O3ceramic tool. Meantime, experiments were conducted to investigate the effect of lubrication methods on the tool wear and surface roughness with the optimized cutting parameters, which can provide references in practical machining.(2) It can be concluded that turning with SiCw-Al2O3ceramic tool can achieve lower surface roughness than that with Sialon ceramic tool with the optimized cutting parameter obtained by the analysis of the orthogonal experiments with the same metal remove volume. Similar result was achieved about the tool wear.(3) After the turning experiments with SiCw-Al2O3ceramic tool, the wear morphology and mechanism were analyzed. Main forms of wear morphology are crater wear, flank wear and notch wear. The wear mechanism are mainly abrasive wear, severe felt wear, chemical wear and diffusion wear. The main forms of tool breakage are micro-chipping, tools surface lost, cracks and cutter edge broken to pieces.(4) The tool wear experiments with different lubrication methods were conducted with SiCw-Al2O3ceramic tool. The lubrication methods include cutting fluids and lower temperature MQL. It was found that the tool life is longer under cutting fluid than that under lower temperature MQL. And the tool life becomes longer with the decrease of the cutting parameters. Meantime, with the decrease of the cutting parameters, the tool life under lower temperature MQL is close to that under cutting fluids.Through the research of surface roughness and tool wear in high-speed turning Inconel718, this paper can get a better ceramic material for Inconel718. At the same time, tool life under different cooling and lubricating modes were studied. This paper provide scientific basis and technique support for high speed machining of Inconel718.