| Vacuum arc ion plating has the advantages of high separation rate and fast deposition rate,and has been applied in the preparation of hard,wear and thermal coatings.However,the technology will produce some large particles deposited in the coating and cause various defects.As the source of plasma and large particles,it directly determines the film forming quality of the whole coating system.Column arc source is the latest traditional arc source and the most advanced.There is the phenomenon of concentrated arc spot etching,which leads to the defects of large particles in the coating,and the stability of arc spot etching and the utilization rate of the target material also have room for improvement.In this paper,the arc control magnetic field in TiAlN coating is applied to study the influence of magnetic field optimization on the tissue structure and mechanical properties of TiAlN coating.First,the existing column arc source magnetic field was simulated by COMSOL software,The magnetic field position near the target material and the distribution of magnetic induction intensity on the target surface are explored,And verified the magnetic field model by experimental measurements,Analysis of the theory of cathode arc spot magnetic field under magnetic field;For the existing column arc source magnetic field problems,Optimize the existing column arc source magnetic field by changing the arrangement of permanent magnets at both ends of the target material and detail the whole process,Explore the magnetic field position shape near the optimized target material and the magnetic induction intensity distribution on the target surface,And the optimized magnetic field model is verified through the experimental measurement;TiAlN coating samples were prepared using column arc sources before and after magnetic field optimization,By comparing the surface and section morphology,hardness and binding force of TiAlN coating,The influence of magnetic field optimization on the tissue structure and mechanical properties of TiAlN coating are discussed.The relevant results of this study are prove to control the arc theory and guide the optimal design of cylindrical arc source magnetic field.The research findings of this paper are as follows:(1)the existing column arc source magnetic field device can form a closed loop distribution of the arch magnetic field,but in the defined arc spot limited area and arc spot stable etching position on the trend of weak ends(the middle part above 18 Gs,only 10～12 Gs),resulting in the target at both ends of the arc spot energy density caused by high concentrated etching,this is also the cause of the groove at the end of the target after each deposition.(2)by changing the arrangement and position of the permanent magnet at both ends of the target,you can improve the arc spot limited area and stable erosion position of transverse magnetic induction intensity(from 10～12 Gs to 18 Gs),optimize the column arc source magnetic field device can still form in the target surface closed loop distribution of arch magnetic field,and the arc spot limited area and the stable erosion position of transverse magnetic induction intensity distribution evenly.(3)After the magnetic field optimization,the number of large particles per unit area of the TiAlN coating surface decreased from 25.72×10~3/mm~2to 20.57×10~3/mm~2,and the average size decreased from 1.83μm to 1.38μm;the internal gap rate of TiAlN coating decreased,tissue uniformity and induced density were improved;the hardness of TiAlN coating increased from 2973 HV to 3230 HV,the combined force increased from 67N to 75N;and the target utilization was also significantly improved. |
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