Material corrosion is a serious problem facing the world

Corrosion not only consumes the precious wealth created by people, but also destroys the normal operation of many activities such as production and life. More and more attention has been paid to the relationship between corrosion and environmental pollution. It is reported that the world's annual direct economic losses caused by corrosion are about 700 billion US dollars, six times the total of natural disasters such as earthquakes, floods and typhoons, accounting for two to four percent of each country's gross national product (GNP). Corrosion loss accounts for 4% of gross national product (GNP) in China, and the number of steel scrapped due to corrosion accounts for 25% ~ 30% of the annual output. The corrosion of production equipment often leads to the shutdown of factories, low labor productivity, rising costs, and even fire, explosion and other safety accidents.

America's Challenger space shuttle, which exploded minutes after liftoff because of a corroded combustion tube, learned this the hard way. In order to prevent corrosion, people have created a variety of anti-corrosion methods, among which coating anti-corrosion is more active. Corrosion prevention is a costly struggle, and the emphasis is on protection. The "impressed current" and "sacrificial anode" in electrochemical protection techniques are very aptly indicative of the addition of corrosion or the sacrifice of some alternative material. Anticorrosive coatings and coating technology is actually looking for coating materials that can take the lead in fighting the dielectric environment, to replace the metal surface, to make it retreat? quot; To protect the metal component or equipment as a whole and its normal operation.

In short, the goal people pursue in the research of anticorrosion technology is not to eliminate corrosion, but to choose to pay a small price to protect the equipment, construction or engineering facilities many times higher than the value of the metal itself. In this paper, the corrosion and protection of materials are discussed based on the corrosion principle and anticorrosion process.