| ZHAO Chunmei,NIU Xinyue,XU Zhengtian,WANG Shaofeng,SHI Zhijun,XING Xiaolei,ZHOU Yefei.Effect of Humidity on Tribological Behavior of a-C:Ti/a-C:Si Nano-multilayer Films[J],53(21):34-43 |
| Effect of Humidity on Tribological Behavior of a-C:Ti/a-C:Si Nano-multilayer Films |
| Received:September 07, 2024 Revised:October 22, 2024 |
| View Full Text View/Add Comment Download reader |
| DOI：10.16490/j.cnki.issn.1001-3660.2024.21.005 |
| KeyWord:multilayer structure a-C:Ti/a-C:Si nano-multilayer films a-C:Si layer mechanical properties tribological properties relative humidity |
| Author | Institution |
| ZHAO Chunmei |
State Key Laboratory of Metastable Materials Science &Technology,Hebei Qinhuangdao , China |
| NIU Xinyue |
School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
| XU Zhengtian |
School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
| WANG Shaofeng |
School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
| SHI Zhijun |
School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
| XING Xiaolei |
School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
| ZHOU Yefei |
State Key Laboratory of Metastable Materials Science &Technology,Hebei Qinhuangdao , China ;School of Mechanical Engineering, Yanshan University, Hebei Qinhuangdao , China |
|
| Hits: |
| Download times: |
| Abstract: |
| The work aims to prepare a-C:Ti/a-C:Si films with nano-scale multilayer structure to improve the humidity adaptability of amorphous carbon films. The a-C:Ti and a-C:Si layers were deposited alternately on the surface of silicon wafer and 304 stainless steel by magnetron sputtering. The sizes of silicon wafer and 304 stainless steel were 10 mm×20 mm×0.33 mm and 12 mm×20 mm×1 mm, respectively. In addition, the cross-sectional morphology and the three-dimensional surface morphology of the films were also characterized. The hardness and elastic modulus of a-C:Ti/a-C:Si nano-multilayer films were determined by nano-indentation tests, and the adhesion between films and substrates was evaluated by the scratch method. The tribological properties of the films were evaluated by tribological tests at different humidity levels with a ball-disk friction and wear tester. Subsequently, the wear marks on the films were analyzed by Raman spectroscopy and scanning electron microscopy. The results showed that the multilayer structure made the interface of the film more complex. With the addition of a-C:Si layer, the hardness, elastic modulus and internal stress of the films increased to 19.6 GPa, 186 GPa and 1.56 GPa, respectively. Moreover, the adhesion of a-C:Ti/a-C:Si nano-multilayer films decreased from 35 N to 25 N compared with a-C:Ti films. The friction coefficient and wear rate of a-C:Ti/a-C:Si nano-multilayer films increased with the increase of a-C:Si layer deposition time, and the wear rate increased to 3.48×10‒16 m3/(N∙m). This was due to the introduced a-C:Si layer, which made it difficult to form carbon transfer films during friction, and it was easier to produce debris. This result was similar to the tribological test results of a-C:Ti/a-C:Si nano-multilayer films at the humidity of 20%. However, when the humidity increased to 80%, this result showed a completely opposite trend. The longer the deposition time of a-C:Si layer, the lower the friction coefficient and wear rate of the film, and the wear rate was as low as 2.2×10‒16 m3/(N∙m). This was because the a-C:Si layer was likely to react with water molecules to form gel compounds SiOx(OH)y, which promoted the formation of silicon-rich transfer films and played a certain role in lubrication. By analyzing the facial distribution of the abrasion spot of the film at the humidity of 80%, it was found that there was a large amount of Si elements distributed on the film, which could confirm that the transfer films produced at this time was a silicon-rich transfer film. The formation of the silicon-rich transfer film reduced the defects of carbon-free transfer films, reduced the friction coefficient and wear rate of a-C:Ti/a-C:Si nano-multilayer films, and improves the tribological properties. At the same time, when the humidity increased from 20% to 80%, the variation of wear rate of a-C:Ti/a-C:Si nano-multilayer films decreased gradually with the a-C:Si layer deposition time, from 3.66×10‒16 m3/(N∙m) to ‒1.4×10‒16 m3/(N∙m), showing good humidity stability. In a word, the nano-multilayer structure effectively enhances the environmental humidity adaptability of a-C films, and makes the films have better tribological properties in the environment with changing humidity. |
| Close |
|
|
|