| It is known that high intense pulsed ion beams (HIPIB) have a high viability to be used as an efficient energetic source for rapid film deposition and direct surface modification. Up to now, however, there is still lack of a systematic work to reveal the influence of HIPIB on the film deposition and material modification although there are lots of papers have been published in the field. In the present work, these two practical applications of HIPIB were all investigated in detail.In the HIPIB film deposition, high purity graphite was employed as target. Relations between process parameters and the microstructure, as well as different physical properties of diamond-like carbon (DLC) film deposited by HIPIB ablated plasma were studied by adjusting the distance between target and substrate, which affects the intensity and ion energy of HIPIB ablated plasma, and the temperature of substrate in the film deposition processes. The mechanism of film deposition by HIPIB ablated plasma was explored also. The experimental results show that DLC film could be deposited on silicon substrate rapidly and uniformly in a large area by means of ablated plasma jet generating on the target surface during HIPIB irradiation, the instantaneous deposition rate is as high as Imm/s and the uniform deposition area covered 40-50 cm2. The as-deposited DLC film exists in amorphous state. The carbon content of sp3 (sp 3C) bonding state in the DLC film is in the range from 8% to 40%. The as-deposited DLC film is rather smooth, with roughness between 0.75nm and 8.4nm. Macro residual stress was formed in DLC film with a pressure value of several GPa. The DLC films were very hard with microhardness between 15 and 30Gpa. The optical band gap (Eg) of deposited DLC film is 0.8-2 eV. The films show also an excellent tribological property with friction coefficient between 0.1 and 0.25. The wear mechanism of DLC film was decided as grain-abrasion wear.It is found that the microstructure and properties of as-deposited DLC films is seriously dependent on the substrate temperature used in deposition processes. With the increase of substrate temperature, sp 3C content in the deposited DLC film decreases, surface roughness and friction coefficient of deposited DLC films increase. At the same time, microhardness, residual stress and optical band gap became lower. The DLC film deposited at substrate temperature of 100癈 shows the best integrated property with carbon content of sp3 (sp 3C) bonding state up to 40% which is two times more than that in the films prepared by Americans with the same method. Accordingly, the microhardness is up to 30Gpa, and friction coefficient and optical band gap decrease to 0.10 and 1.76eV respectively. It is found that sp3C content in DLC films decreases with the increasing substrate temperature in the process of film deposition, especially after 300癈. It is verified that the temperature of graphitization increases up to 300癈 in the film deposition by HIPIB ablated plasma, which is much higher than the other film deposition methods with graphitization temperature of less than 200癈.Moreover, it was found that the microstructure and physical properties of DLC film were affected to some extent by the distance between target and substrate. When the distance between target and substrate increases, sp 3C content in the deposited DLC film decreases. Accordingly, the value of surface roughness, microhardness, friction coefficient, residual stress and band gap became lower in the same way.In the HIPIB strengthening experiments, samples of high-speed steel (W6Mo5Cr4V2) were irradiated byABSTRACTHIPIB (Cn+=30%, H+=70%, ion energy 250 keV, ion current density 60-180A/cm2, pulse duration 80-100 ns). Microstructure investigation and properties characterization of the treated HSS samples were carried out to investigate the effect of current density and pulse number of incident HIPIB on the surface modification treatment. The physical mechanism of the HIPIB-solid interaction was established based on the experiments.T...
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