by: Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences

The significant improvement of the cavitation resistance of metal surfaces has become an inevitable requirement for the long life and high reliability of service equipment in fluid media. With the help of various surface coating technologies, it is the field of material surface engineering to optimize and improve the cavitation resistance of materials Research hotspots. As a special phenomenon of material damage, cavitation is especially complicated due to the coupling interaction of "corrosion-cavitation" caused by the occurrence, occurrence and serious damage of cavitation caused by the material in the seawater medium.

The abrasion and surface engineering and polymer tribology research group of the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences used thermal spraying technology and used Ni-based alloy powders with excellent high temperature and corrosion resistance to prepare related cavitation resistant coating materials. The mechanism of the coating crystal structure evolution, physical phase and microstructure improvement to improve the cavitation resistance of the coating in artificial seawater was revealed; the interaction between the corrosion film formed on the coating surface and the cavitation performance of the coating was studied and deepened Analysis; through electrochemical testing of the coating cavitation plaque area, the electrochemical corrosion mechanism of cavitation damage was analyzed.

Studies have shown that in seawater media, the mechanical properties of the coating material itself and the improvement of micro-defects in the coating can improve the cavitation resistance of the coating; the improvement of the corrosion resistance will alleviate the damage process of cavitation. With the coupling effect of cavitation, corrosion will aggravate the cavitation damage, but the resulting material failure is still mainly caused by cavitation damage.

The above research results were recently published in Corrosion Science, Journal of Materials Science & Technology and Applied Surface Science.

The above work was supported by outstanding members of the "Youth Innovation Promotion Association" of the Chinese Academy of Sciences and the National Natural Science Foundation of China.

Progress in research on cavitation resistant coating materials

Advances in research on cavitation-resistant coating materials at Lanzhou Chemical Institute

Editor in charge: Ye Ruiyou

Source:  http://www.cas.ac.cn/syky/202005/t20200525_4747693.shtml