| With the increasing demand for all kinds of materials with high hardness and high strength in aerospace,shipbuilding and other fields,it is urgent to solve the problem of short tool life and low processing efficiency.Reasonable selection of coating materials is an effective way to solve difficult problems.Multi coating tools have been widely concerned because of their high hardness,wear resistance and good high temperature stability.In order to further improve the mechanical properties and oxidation resistance of coating,the focus of research has focused on the multi coating system and process parameters of multi-component coating and multicomponent nitride coatings and multiple nitrogen oxide coating tool cutting performance and does not see more research on tool wear.In this paper,a series of AlCrSiN coatings were prepared by the arc ion plating technique on stainless steel,monocrystalline silicon and other substrates by changing the bias of the DC substrate.Then,by changing the O2/（N2+O2）gas flow ratio to develop AlCrSiON coating.The microstructure,mechanical properties and friction and wear properties of the two coatings were studied by scanning electron microscopy（SEM）,X-ray diffractometry（XRD）,nanoindentation and pin-plate tribometer.The AlCrSiON coating with the O2/（N2+O2）gas flow ratio of 19.05%was normalized using a muffle furnace to investigate its high temperature thermal stability.According to the above experiment,AlCrSiN coating,AlCrSiON coating and AlCrSiN/AlCrSiON composite coating were deposited on the surface of high speed steel cutting tools by using the optimized technological parameters.The cutting force and tool wear of uncoated cutting tools and coated tools of different systems were compared.1.The arc ion plating technique was used to deposit AlCrSiN coating under different DC bias voltages to study the effect of substrate bias on the composition,microstructure and properties of the coatings.The results show that AlCrSiN coating mainly consists of a hexagonal close-packed hexagonal structure and a face-centered cubic AlN phase.With the increase of the substrate negative bias,the diffraction peak of the coating shifts to a small angle.The residual compressive stress in the coating gradually increases Increase,the maximum value of-0.77GPa;coating hardness and friction coefficient change is not obvious.When the negative bias of the substrate is-40V,the characteristic parameters H/E and H3/E*2 of AlCrSiN coating reach the maximum values of 0.1475 and 0.3681GPa,respectively.At this time,the coating has the best wear resistance and the friction coefficient is also the lowest.2.A series of AlCrSiON coatings with different oxygen content were prepared in the atmosphere of Ar/N2/O2 gas mixture.The results showed that when the flow rate of O2/（O2+N2）increased from 0 to 19.05%,the oxygen content in the coating increased from 0 to 14.3%,while the nitrogen content decreased from 100%to 60.7%.When the flow rate of O2/（O2+N2）is11.43%,the diffraction peaks of Al2O3 and Cr2O3 appear.With the increase of oxygen content,the hardness and elastic modulus of AlCrSiON coating change the same trend.The maximum value is 17.87Gpa and 179.75Gpa respectively.The average friction coefficient of the coating increases first and then decreases.The maximum value is about 0.88.The presence of oxide reduces the friction coefficient of the coating and improves the oxidation resistance,but it is worn because of the large brittle coating.The crack quality of the coating after heat treatment at1100℃is reduced and the failure of the coating is reduced.3.AlCrSiN,AlCrSiON and AlCrSiN/AlCrSiON composite coatings were deposited on the surface of high-speed steel cutting tools with the optimized process parameters for the cutting experiments of 45#steel.The results show that the coating tool can effectively reduce the tool wear and prolong the tool life.AlCrSiN coated end mills not only have a stable low cutting force and good wear resistance,AlCrSiON coated end mills have good thermal stability,can be used for cutting temperature is relatively high occasions. |
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