英语翻译
Thecoatingofzincservestwopurposes:firstlyitcoverstheironandpreventsitsoxidation(ratherlikeacoatofpaint)andsecondlyitprovidesanodicprotection.Ifthegalvanizedsteelisscratched,allowingtheairtooxidizesomeiron,theFe2+producedisimmediatelyreducedtoironbythezinc,andrustingdoesnotoccur.Similarapplicationsinwhichonemetalissacrificedtoprotectanotheraretheattachingofsacrificialblocksofmagnesiumtoundergroundsteelpipelinesandthehullsofshipstopreventtherustingofiron.
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