A diamond-like carbon（DLC） film was deposited on YT14 substrate using magnetron sputtering（MS）. The surface morphologies, roughness and bonding spectra of obtained film were characterized using scanning electron m...A diamond-like carbon（DLC） film was deposited on YT14 substrate using magnetron sputtering（MS）. The surface morphologies, roughness and bonding spectra of obtained film were characterized using scanning electron microscopy（SEM）, atomic force microscopy（AFM）, and X-ray photoelectron spectroscopy（XPS）, respectively, and its mechanical property and bonding strength were measured using a nanoindentation and scratch tester, respectively. The results show that the C-enriched DLC film exhibits a denser microstructure and smoother surface with lower surface roughness of 21.8 nm. The ratio of C sp2 at 284.4 e V that corresponds to the diamond（111） and the C sp3 at 285.3 e V that corresponds to the diamond（220） plane for the as-received film is 0.36： 0.64, showing that the C sp3 has the high content. The hardness and Young＇s modulus of DLC film by nanoindentation are 8.534 41 and 142.158 1 GPa, respectively, and the corresponding bonding strength is 74.55 N by scratch test.展开更多
Preparation of titanium film on magnesium substrate faces a challenge due to non-Fickian inter-diffusion between titanium and magnesium. Aluminum can build a bridge between titanium and magnesium. Al/Ti duplex coating...Preparation of titanium film on magnesium substrate faces a challenge due to non-Fickian inter-diffusion between titanium and magnesium. Aluminum can build a bridge between titanium and magnesium. Al/Ti duplex coatings were deposited on magnesium alloy AZ31B using magnetron sputtering （MS）. The low temperature diffusion bonding behavior of the MglAl/Ti coating was investigated through SEM and its affiliated EDS. The phase structure and critical load of the coatings were examined by means of XRD and scratch tests, respectively, The results demonstrated that the bonding strength was significantly improved after a post heat treatment （HT） at a temperature of 210℃. The diffusion mechanism of the interfaces of MglAI and Al/Ti in the coating was discussed based on the analysis of formation energy of vacancies and diffusion rates. The Al/Ti dual layer enhanced the corrosion resistance of the alloy. And the HT process further increased the corrosion resistance of the coated alloy. This result implies that a post HTat a lower temperature after MS is an effective approach to enhance the bonding strength and corrosion resistance of the Al/Ti film on Mg alloys.展开更多
基金Funded by the Jiangsu Province Science and Technology Support Program(Industry)(No.BE2014818)
文摘A diamond-like carbon（DLC） film was deposited on YT14 substrate using magnetron sputtering（MS）. The surface morphologies, roughness and bonding spectra of obtained film were characterized using scanning electron microscopy（SEM）, atomic force microscopy（AFM）, and X-ray photoelectron spectroscopy（XPS）, respectively, and its mechanical property and bonding strength were measured using a nanoindentation and scratch tester, respectively. The results show that the C-enriched DLC film exhibits a denser microstructure and smoother surface with lower surface roughness of 21.8 nm. The ratio of C sp2 at 284.4 e V that corresponds to the diamond（111） and the C sp3 at 285.3 e V that corresponds to the diamond（220） plane for the as-received film is 0.36： 0.64, showing that the C sp3 has the high content. The hardness and Young＇s modulus of DLC film by nanoindentation are 8.534 41 and 142.158 1 GPa, respectively, and the corresponding bonding strength is 74.55 N by scratch test.
基金Acknowledgements This research was financially supported by the National Natural Science Foundation of China （Grant No. 51241001）, Shandong Provincial Natural Science Foundation, China （ZR2011 EMM004）, Taishan Scholarship Project of Shandong Province （TS20110828）, SDUST Research Fund （2014TDJH104）, Joint Innovative Center for Safe and Effective Mining Technology and Equipment of Coal Resources, and Shandong Province. Thanks go to Dr. Jun CHEN, Dr. Donghua YANG and Dr. Zhenlin WANG in Chongqing University of Technology for the help in the sample preparation, corrosion and scratch tests.
文摘Preparation of titanium film on magnesium substrate faces a challenge due to non-Fickian inter-diffusion between titanium and magnesium. Aluminum can build a bridge between titanium and magnesium. Al/Ti duplex coatings were deposited on magnesium alloy AZ31B using magnetron sputtering （MS）. The low temperature diffusion bonding behavior of the MglAl/Ti coating was investigated through SEM and its affiliated EDS. The phase structure and critical load of the coatings were examined by means of XRD and scratch tests, respectively, The results demonstrated that the bonding strength was significantly improved after a post heat treatment （HT） at a temperature of 210℃. The diffusion mechanism of the interfaces of MglAI and Al/Ti in the coating was discussed based on the analysis of formation energy of vacancies and diffusion rates. The Al/Ti dual layer enhanced the corrosion resistance of the alloy. And the HT process further increased the corrosion resistance of the coated alloy. This result implies that a post HTat a lower temperature after MS is an effective approach to enhance the bonding strength and corrosion resistance of the Al/Ti film on Mg alloys.
