Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating
Porosity is closely related to the corrosion and wear properties of a coating processed by thermal-spraying technology, and the quantitative characterization of porosity is a crucial part of the research on coating structures. The current image analysis method often uses the mechanical polishing met...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-10-01
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| Series: | Materials |
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| Online Access: | https://www.mdpi.com/1996-1944/16/19/6612 |
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| author | Bo Li Lei Fan Jie Bai Jinhang He Jianfeng Su Song Wang Chao Deng Shifeng Liu Zhiqing Zhang |
| author_facet | Bo Li Lei Fan Jie Bai Jinhang He Jianfeng Su Song Wang Chao Deng Shifeng Liu Zhiqing Zhang |
| author_sort | Bo Li |
| collection | DOAJ |
| description | Porosity is closely related to the corrosion and wear properties of a coating processed by thermal-spraying technology, and the quantitative characterization of porosity is a crucial part of the research on coating structures. The current image analysis method often uses the mechanical polishing method recommended by ISO to measure a coating porosity. This method has been proved to be an effective method for the characterization of oxide coatings. However, due to the significant differences in the physical and chemical properties between aluminum and oxides, this method may not be suitable for aluminum coatings, and a more appropriate approach needs to be explored. In this paper, the effects of three polishing technologies (mechanical polishing, argon-ion-beam polishing, and electrolytic polishing) on the porosity measurement of pure aluminum coatings were compared and studied. The research results showed that the commonly used mechanical polishing method and more advanced argon-ion-beam polishing method could not completely reveal the pore structure because SiC particles would be embedded in the pure aluminum coatings during mechanical polishing, filling large pores. Although electrolytic polishing technology had advantages in revealing the macroporous structure, it would introduce a microporous structure and oxides, which would affect the measurement of the coating porosity. The composite polishing technology (electrolytic polishing + argon-ion-beam polishing) could perfectly reveal the pore structure in the pure-aluminum coating, and the porosity of arc-sprayed aluminum coating was 9.9%, which was close to the macroscopic true value measured using the weighing method of 10.2%. |
| first_indexed | 2024-03-10T21:40:42Z |
| format | Article |
| id | doaj.art-59c008a295614bd1b9296c8ceb5511d0 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-10T21:40:42Z |
| publishDate | 2023-10-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-59c008a295614bd1b9296c8ceb5511d02023-11-19T14:42:15ZengMDPI AGMaterials1996-19442023-10-011619661210.3390/ma16196612Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum CoatingBo Li0Lei Fan1Jie Bai2Jinhang He3Jianfeng Su4Song Wang5Chao Deng6Shifeng Liu7Zhiqing Zhang8Electric Power Research Institute, Guizhou Power Grid Co., Ltd., Guiyang 550000, ChinaElectric Power Research Institute, Guizhou Power Grid Co., Ltd., Guiyang 550000, ChinaElectric Power Research Institute, Guizhou Power Grid Co., Ltd., Guiyang 550000, ChinaElectric Power Research Institute, Guizhou Power Grid Co., Ltd., Guiyang 550000, ChinaAn Shun Power Supply Bureau, Guizhou Power Grid Co., Ltd., Anshun 561000, ChinaCollege of Materials Science and Engineering, Chongqing University, Chongqing 400044, ChinaCollege of Materials Science and Engineering, Chongqing University, Chongqing 400044, ChinaCollege of Materials Science and Engineering, Chongqing University, Chongqing 400044, ChinaCollege of Materials Science and Engineering, Chongqing University, Chongqing 400044, ChinaPorosity is closely related to the corrosion and wear properties of a coating processed by thermal-spraying technology, and the quantitative characterization of porosity is a crucial part of the research on coating structures. The current image analysis method often uses the mechanical polishing method recommended by ISO to measure a coating porosity. This method has been proved to be an effective method for the characterization of oxide coatings. However, due to the significant differences in the physical and chemical properties between aluminum and oxides, this method may not be suitable for aluminum coatings, and a more appropriate approach needs to be explored. In this paper, the effects of three polishing technologies (mechanical polishing, argon-ion-beam polishing, and electrolytic polishing) on the porosity measurement of pure aluminum coatings were compared and studied. The research results showed that the commonly used mechanical polishing method and more advanced argon-ion-beam polishing method could not completely reveal the pore structure because SiC particles would be embedded in the pure aluminum coatings during mechanical polishing, filling large pores. Although electrolytic polishing technology had advantages in revealing the macroporous structure, it would introduce a microporous structure and oxides, which would affect the measurement of the coating porosity. The composite polishing technology (electrolytic polishing + argon-ion-beam polishing) could perfectly reveal the pore structure in the pure-aluminum coating, and the porosity of arc-sprayed aluminum coating was 9.9%, which was close to the macroscopic true value measured using the weighing method of 10.2%.https://www.mdpi.com/1996-1944/16/19/6612coatingmechanical polishingargon ion beamelectrolytic polishingporosity |
| spellingShingle | Bo Li Lei Fan Jie Bai Jinhang He Jianfeng Su Song Wang Chao Deng Shifeng Liu Zhiqing Zhang Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating Materials coating mechanical polishing argon ion beam electrolytic polishing porosity |
| title | Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating |
| title_full | Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating |
| title_fullStr | Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating |
| title_full_unstemmed | Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating |
| title_short | Study on Porosity of Thermal-Sprayed Commercially Pure Aluminum Coating |
| title_sort | study on porosity of thermal sprayed commercially pure aluminum coating |
| topic | coating mechanical polishing argon ion beam electrolytic polishing porosity |
| url | https://www.mdpi.com/1996-1944/16/19/6612 |
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