The Cutting Performance Study On Coated Cutting Tool In Machining

Now in machining operations, some cutting tools are widely used such as high strength, high hardness, high heat resistance and high wear resistance materials. The machining difficulty is also constantly increased. With this kind of situation, the development of the cutting tool is changed with each passing day and the product processing quality has been improved. The coating tool occupies a big market. The reason is rooted in more excellent coating can improve the tool surface performance,which make the thermal insulation properties, high temperature hardness, thermal stability, impact toughness and resistance to chemical corrosion, fatigue resistance greatly improved. At the same time, the tool cutting speed and service life are also gotten effective improvement. Along with the progress of the science and technology,all kinds of coated cutting tool and cutting method is appeared and replaced. It is a new problem to choose an effective rigid alloy coated cutting tool in a wide variety of tools.Through the cutting experimental method, the die steel(Cr12MoV) materials and austenitic stainless steel materials(321) are machining with the application of carbide coating tool in different processing mode. High-precision XH715 D machining center, HTC32 numerical control machine tool and general CA6140 lathe are applied in the experiment. The machining scheme does many cutting experiments by adjusting the three factors of the cutting quantity such as cutting speed vc, feed rates f and milling depth ap. In the experimental process, a lot of high-precision test instruments and equipments are used to do real-time processing and record the data.Adopting the S-4700 ice emission scanning electron microscopy, EDAX PV9900 energy spectrum instrument and JC4-10 reading microscope, the specimen cutting, carbide coating tools failure and abrade parts are analysed and compared to research the abrade mechanism and failure characterization of different cemented carbide coating tools. The micrograph of the cemented carbide coating tools’ abrade area is obtained to construct force analysis chart and generate energy spectrum diagram. By comparing the figure and chart generated by different process factors, the strategy is discussed how to select the excellent process factors, the coating material’s structure and the best process method. The multiple elements and the rational use of range are put forward while different coated tools processing different materials.Through analysis, the following conclusion can be acquired. The machining quality is good with dry milling when cutting die steel(Cr12MoV) by the PVD process AlTiN(nitrogen titanium aluminum) coating tool. In the different process and composition of the AlTiN coating, AlTiN + Si3N4(nano composite phase structure coating) coating tool can get higher machining quality with high cutting speed, small optimizing depth and feed back to die steel finishing. When cutting austenitic stainless steel(321), the composite coating tool life of the CVD TiCN + A12O3 + TiN is less than the PVD TiN + TiAlN. The stability of TH- CVD TiN + TiAlN coated tools is slightly inferior than MT- CVD TiN + TiAlN coatings tool in the metal cutting process. Adding appropriate AL in the tool coating can improve the performance of cutting tool and extend the life of the cutter. The stability of the coated tools with PVD coating technology is better than that with CVD coating technology.