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一、金属的腐蝕金属的腐蝕有两种过程,一种是化学过程,一种是电化学过程。前者是在非电解質或干燥气体中发生的,如金属在液体燃料中的腐蝕。金属在純石油中实际是不发生腐蝕的,但有硫化物杂質存在时,便会对很多金属起腐蝕作用;裂化汽油亦能引起某些金属的剧烈腐蝕。金属在干燥空气中,也能与空气中的氧作用而生成一层很薄的氧化鉄。倘这层膜是完整而紧密的,氧就不容易透过薄膜而与鉄表面起作用,因此腐蝕的速度减慢。氧化膜的厚度随时間而成抛物綫增加,但如膜疏松或不完整,那末氧化膜的厚度便随时間而成直綫增長。空气中除氧对金属有影响外,一氧化碳与二氢化硫对它也有很大的損坏作用。化学腐蝕系金属与腐蝕介質直接作用而沒有电流发生。电化学腐蝕的过程是比較复杂的,但也是金属腐蝕中最常見的一
First, the corrosion of metals Metal corrosion has two processes, one is the chemical process, one is the electrochemical process. The former occurs in non-electrolytes or dry gases, such as corrosion of metals in liquid fuels. Metals actually do not corrode in pure petroleum, but when sulfide impurities are present, they can corrode many metals; cracking gasoline can also cause severe corrosion of some metals. Metal in dry air, but also with the role of oxygen in the air and generate a thin layer of oxide 鉄. If the film is intact and tight, the oxygen will not readily penetrate the film and interact with the surface, so corrosion will slow down. The thickness of the oxide film increases parabolically over time, but if the film is loose or incomplete, then the thickness of the oxide film increases linearly with time. In addition to oxygen in the air have an impact on the metal, carbon monoxide and sulfur dihydrogen sulfide on it also has a great damaging effect. Department of chemical corrosion of metals and corrosive media directly without the occurrence of current. Electrochemical corrosion process is more complex, but it is also the most common metal corrosion