4:00 PM - 4:15 PM
△ [15p-F203-10] Tribological properties of carbon nanotube reinforced copper composite fabricated by cold spray
Keywords:Carbon nanoutbe, Composite, Cold spray
Carbon nanotubes (CNTs) application in various composite materials owes to its outstanding physical, chemical and electrical properties as filler. CNT filler brings drastic change in mechanical and electro-conductive properties in the base materials. In this research, we adopted a cold spray processing technique to prepare a Cu composite film on Al substrate, where Cu powder and CNT mixture is used as source material. The target of the research is quick and easy deposition of Cu/CNT composite films which has minimized oxidative stress and corrosion. The thermal and electric conductivities of the CU/CNT composite film was examined and the effect of CNT filler was discussed.
The base Cu powder was purchased from Senshin Enterprise Co., Ltd, its mean particle size was 20 mm in diameter. The CNT used as filler was multi-walled CNT “VGNF” from Showa Denko. CNT mixing ratio in source material was 1.0 wt. %. Cold spray apparatus DYMET 423 from OCPS was used for composite film deposition. Spray gas pressure was set at 0.57 MPa, feeding rate was 10 g/min, gas temperature was controlled at 275 ℃, and distance between nozzle and substrate was kept at 12 mm. The width of Cu/CNT composite film obtained by cold spray deposition for about 10 min. was 15 mm × 75 mm, and the mean thickness of the film was about 3 mm. Then the composite film obtained was examined by a laser Raman spectroscopy, where the laser intensity was fixed at 3.1 mW and an excitation wavelength was 532 nm. The Raman scattering peaks observed on the composite film were attributed to Cu and CNT, suggesting both Cu and CNT were integrated in the composite films without any mechanical damage during the course of cold spray operation. Based on the Raman spectra, the Cu/CNT composite film formation by cold spray processing was confirmed. The increased electrical conductivity compare with Cu film was also confirmed by conduction tester. That was further evidence of the incorporation of CNT in Cu film. In conclusion, Cu/CNT composite film formation on Al substrate was successfully achieved by adopting the cold spray processing.
For measuring Friction coefficient, Ball on Disk method was applied. that friction coefficient was reduced when CNT was mixed in Cu film compared with Cu film. It was suggested that CNT mixed Cu film is able to reduce friction coefficient by CNT’s characteristics of self-lubrication.
The base Cu powder was purchased from Senshin Enterprise Co., Ltd, its mean particle size was 20 mm in diameter. The CNT used as filler was multi-walled CNT “VGNF” from Showa Denko. CNT mixing ratio in source material was 1.0 wt. %. Cold spray apparatus DYMET 423 from OCPS was used for composite film deposition. Spray gas pressure was set at 0.57 MPa, feeding rate was 10 g/min, gas temperature was controlled at 275 ℃, and distance between nozzle and substrate was kept at 12 mm. The width of Cu/CNT composite film obtained by cold spray deposition for about 10 min. was 15 mm × 75 mm, and the mean thickness of the film was about 3 mm. Then the composite film obtained was examined by a laser Raman spectroscopy, where the laser intensity was fixed at 3.1 mW and an excitation wavelength was 532 nm. The Raman scattering peaks observed on the composite film were attributed to Cu and CNT, suggesting both Cu and CNT were integrated in the composite films without any mechanical damage during the course of cold spray operation. Based on the Raman spectra, the Cu/CNT composite film formation by cold spray processing was confirmed. The increased electrical conductivity compare with Cu film was also confirmed by conduction tester. That was further evidence of the incorporation of CNT in Cu film. In conclusion, Cu/CNT composite film formation on Al substrate was successfully achieved by adopting the cold spray processing.
For measuring Friction coefficient, Ball on Disk method was applied. that friction coefficient was reduced when CNT was mixed in Cu film compared with Cu film. It was suggested that CNT mixed Cu film is able to reduce friction coefficient by CNT’s characteristics of self-lubrication.