Fabrication And Strengthen-toughening Research For Ti-Cu-N Nanocomposite Films

The Ti-Cu-N nanocomposite films with different Cu content were prepared with arc ionplanting technology through changing the deposition pulse bias and using Ti-Cu alloytargets which contains5.0at%,10.0at%and15.0at%Cu respectively. Some of thesedeposited films were aging heat-treated at different time in400℃. The microstructure andproperties of the studied films were analyzed and tested, respectively.The energy spectrum analysis show that with decreasing the negative deposition biasfrom300V to0V, the Cu content in deposited Ti-Cu-N films gradually increases. But thebiggest Cu content in deposition film is obviously less than the Cu content in Ti-Cu alloytarget. For every Ti-Cu alloy target with different Cu contents, the Cu content in depositedfilm slightly varies with changing negative bias value. X-ray diffraction spectrum showthat only TiN phase diffraction peak of deposited film occurs in the XRD pattern. Themetal Cu phase or Cu compound phase diffraction peak does not still occur even if the Cucontent in deposited thin film is as high as7.95at%. The calculation of the grain size indeposited film by the half high width of the diffraction peak show that the grain size ofTiN phase is very small and it is in the order of nanometer magnitude. The average grainsize of TiN phase slightly reduces with increasing Cu content in deposition film. Its grainsize varies from12.99nm for pure TiN film to6.77nm for the film with4.74at%Cucontent. Pure TiN film has obvious (111) crystal plane preferred orientation. But forcontaining Cu deposition film, the relative intensity of (220) crystal plane diffraction peakof TiN phase gradually reduces and the relative intensity of (111) crystal plane diffractionpeak of TiN phase enhances with the increase of the Cu content in deposited film. Thissuggests that the preferred orientation transform from the (220) crystal plane into (111)crystal plane with increasing the Cu content in deposition film. The hardness of depositionfilm is influenced by Cu content in the film. With increasing Cu content, film hardnessslowly increases. When Cu content is2.33at%, film hardness reaches a maximum of2686HV. Further increasing the Cu content in film, film hardness greatly decreases. In the range of studied aging time and Cu content, the hardness of the film slightly increases withincreasing aging time for the films up to4.74at%Cu content.The hardness of deposited film increases first, reaches a maximum value and decreaseswith increasing aging time for the films more than4.74at%Cu content. After aging, anynew phase does not occur in the XRD pattern and metal Cu phase or Cu compound phasedoes not also occur. In addition, the preferred orientation of the film transforms from (220)crystal plane into (111) crystal plane for Cu5Ti95alloy target with extending the agingtime.The indentation experiments show that the indentation depth is about10μm subjected a10kg force. However, there are still no cracks at the indentation corner for all tested film,this suggest that the deposition film has high toughness.