Preparation Of TiN-Cu Based Hydrophobic Films By Multi Arc Ion Plating

TiN films are a kind of hard film with excellent and mature properties,which is widely used in cutting tools,molds,geological drilling,textile industry,medical devices,automobile manufacturing and other fields.However,with the development of industry,its performance can not meet the requirements of users.In order to improve the properties of TiN films,researchers have carried out research in many aspects.The first,it is the optimization of the preparation process and the new preparation technologies,such as,magnetron sputtering,multi arc ion plating,HiPIMS and other technologies;the second,it is the optimization of the film structure,such as,Ti/TiN multilayer films,Ti/TiN nano multilayer films;the last,it is the optimization of the film composition,such as,the targeted preparation of TiCN films with C element has lower friction coefficient and higher friction coefficient hardness,the TiAlN films prepared by adding Al element has good oxidation resistance,and the tin Cu film prepared by adding Cu element has high hardness and good hydrophobicity.In this paper,SiAlON/Cr buffer layer was prepared on quartz glass substrate by magnetron sputtering and multi arc ion plating.TiN-Cu single-layer film,TiCu/TiN-Cu composite multilayer film with TiCu buffer layer were prepared by multi arc ion plating.The content of Cu,modulation ratio and modulation period are studied.The results are as follows:(1)Five groups of TiN-Cu flims,with different content of Cu from 0.76at%to 4.51at%,were prepared on the quartz glass substrate by multi arc ion plating.The cross section of TiN-Cu films are fine and compact,and typical columnar crystal structure of TiN film is not observed.With the increase of Cu content,the hardness of the film first increased and then decreased.As the Cu content is 0.76 at%,the hardness of the film is the lowest,which is 29.03GPa.As the Cu content is 3.04at%,the hardness of the film is the highest,which is 34.32GPa.The hardness of the TiN-Cu films are higher than TiN films.The Cu inhibited the growth of TiN grains and refined the grains.The hardness of the films increased due to Hall-Petch effect.However,when the content of Cu is too high,the soft Cu has a negative effect on the hardness of TiN-Cu films.The results show that the adhension of the films increased first and then decreased,which is consistent with the H3/E2 values of the films.The H3/E2 values represent the fracture toughness of the films.The better the fracture toughness is,the higher the adhension of the film is.The hydrophobicity of TiN-Cu films increased slightly with the increasing of Cu content,and the Cu-0 bond formed by the oxidation of Cu is the reason for the better hydrophobicity of TiN-Cu films.As the Cu content was 4.51 at%,the contact angle of the films was the highest,which is 102.1°.However,the hydrophobicity of TiN-Cu film was not obviously increased with the increase of Cu content,and the contact angle is in the range of 100.5°～102.1 0.(2)SiAlON/Cr buffer layer was prepared on the quartz glass substrate by magnetron sputtering,and TiCu/TiN-Cu nano multilayer composite films with modulation ratio of 0.333～0.833 were prepared on the SiAlON/Cr buffer layer by multi arc ion plating.The Cu and nano multilayered structure inhibite the growth of TiN grains,which resulted in the disappearance of columnar crystals.The surface quality of the films has been significantly improved because of the optimizing of the experimental parameters.The hardness,modulus and fracture toughness of the films decreased first,then increased,and then decreased with the increase of the modulation ratio,which is caused by Hall-Petch effect and modulus difference effect.As the modulation ratio is 0.333,the growth of TiN grains are inhibited by the introduction of TiCu layer,so the hardness of TiCu/TiN-Cu nano multilayer is slightly higher than the hardness of TiN-Cu films due to the Hall-Petch effect.As the modulation ratio is 0.458,the hardness of the films is the lowest,which is 23.92GPa,which is lower than the hardness of TiN-Cu films.The reason is the forming of the Cu+TixN1-x mixed layer between the two TiN-Cu layers,and there are more dislocations and other defects in the mixed layer,so the hardness is decreased.As the modulation ratio continues to increase,an effective TiCu layer is formed,the modulus difference effect begins to play a role,and the hardness of the films increases.As the modulation ratio is 0.708,the hardness of the film is highest,which is 40.89GPa,and the corresponding contact angle is 100.0°,while the contact angle of TiN films is generally between 70°and 90°.As the modulation ratio continues to increase,the soft TiCu layer is too thick,resulting in the hardness decreased to 22.97GPa.As the increase of the modulation ratio,the adhension of the film increases first and then decreases,which is caused by the the change of fracture toughness and the modulus of the films.The hydrophobicity of the films is basically the same as the hydrophobicity of TiN-Cu films.(3)SiAlON/Cr buffer layer was prepared on the quartz glass substrate by magnetron sputtering,TiCu/TiN-Cu multilayers with different modulation periods were prepared on the SiAlON/Cr buffer layer by multi arc ion plating,and TiCu layer was used as stress relaxation layer.Due to the low content of Cu and the large modulation period,the inhibiting on the growth of TiN grains is poor;so there is not obvious columnar crystal structure in the film section.Metal particles mainly accumulate in the deposition time of metal layer.Due to the short deposition time of TiCu stress relaxation layer in TiCu/TiN-Cu multilayer film,the surface quality of the films is woser than the TiN-Cu films,but better than TiCu/TiN-Cu nano multilayer composite films.The introduction of TiCu stress relaxation layer did not significantly improve the hardness and hydrophobicity of the films.The hardness of the films is between 26.67GPa and 33.63GPa,and the contact angle is between 88.5°and 95.1°,all of which were in the normal range of TiN-Cu films.The main function of TiCu stress relaxation layer is to reduce the transverse stress between the films and the substrates,the shift of TiN(111)peaks in the XRD spectrum shows this,and the adhension of the flims is also slightly increased.The adhension of TiN-Cu films is 24.9N,but the adhension of TiCu/TiN-Cu multilayers is between 26.15N and 27.68N.After ultrasonic testing and annealing at 600℃ for 3 hours and then ultrasonic testing,the results show that the combination of films and substrates of TiCu/TiN-Cu multilayers is better than that of TiN-Cu films.