鍍鋅板卷會生銹嗎？

Will the galvanized sheet roll rust?

那要看表面受損的程度，如果只是輕微的磨損，不會造成太大的影響，如果磨損較為嚴(yán)重露出了里面的鋼材，那么就可能會引起生銹的情況。所謂不會生銹就是具有大氣耐腐蝕性。

It depends on the degree of surface damage, if it is only a slight wear, will not cause too much impact, if the wear is more serious to expose the steel inside, then it may cause rust. The so-called will not rust is with atmospheric corrosion resistance.

為什么鍍鋅鋼板具有耐腐蝕性？

Why does galvanized steel plate have corrosion resistance?

1）鍍鋅以后鍍層是完好的

1) The coating is intact after galvanizing

由于鋅將空氣與鋼基隔絕了開來，只發(fā)生鋅的腐蝕，由于鋅腐蝕的產(chǎn)物對鋅有較好的保護作用，所以腐蝕速度非常慢，壽命是未鍍鋅鋼板的15～30倍。

Because zinc isolates air from steel base, only the corrosion of zinc occurs. Because the product of zinc corrosion has a good protection effect on zinc, the corrosion speed is very slow, and the life is 15~30 times that of ungalvanized steel plate.

例如，在中性或弱酸性(pH>5.2)的大氣環(huán)境下， 鋼板鍍鋅層經(jīng)腐蝕后形成的濁產(chǎn)物為非溶性化合物(氫氧化鋅、氧化鋅和碳酸鋅)，這些產(chǎn)物將以沉淀形式析出，形成致密的薄層，一般可達(dá)8μm厚度。這種薄膜既有一定厚度又不容易溶解于水，附著性又很強，因此它能起到隔離大氣和鍍鋅板的屏障作用，防止腐蝕進(jìn)一步發(fā)展。

For example, in a neutral or weakly acidic (pH> 5.2) atmospheric environment, the corrosion formation of non-soluble compounds (zinc hydroxide, zinc oxide and zinc carbonate), these products will precipitate to form a dense thin layer, generally up to 8 μ m thickness. This film has a certain thickness and is not easy to dissolve in water, and the attachment is very strong, so it can play a barrier to isolate the atmosphere and galvanized plate, to prevent the further development of corrosion.

2）如果鋅層被被破壞了，犧牲腐蝕作用

2) If the zinc layer is destroyed, sacrifice the corrosion effect

鍍層中的鋅與鋼帶中的鐵在潮濕的環(huán)境中組成了原電池，由于鋅的標(biāo)準(zhǔn)電極電位只有-1.05V，低于鐵的-0.036V，因而鋅作為陽極被氧化，而鐵作為陰極得到保護。由于鋅腐蝕以后的生成物很致密，反應(yīng)速度很慢，也就是說總體的耐腐蝕性能大幅度提高。這種防腐方法叫犧牲防腐。

The zinc in the coating and the iron in the steel belt constitute the primary cell in the humid environment. Because the standard electrode potential of zinc is only-1.05V, lower than the-0.036V, the zinc is oxidized as the anode and the iron is protected as the cathode. Because the generation after zinc corrosion is very dense, the reaction speed is very slow, that is to say, the overall corrosion resistance is greatly improved. This anticorrosion method is called sacrificial anticorrosion.

鍍層損傷后，由于犧牲腐蝕作用，鋼基同樣也會得到保護，但是如果損傷達(dá)到鋼基，鋼基受損后，犧牲保護作用將變?nèi)?，所以較深的損傷一定要進(jìn)行防銹處理（涂漆等），避免進(jìn)一步銹蝕。在保護鍍鋅層遭到破壞，鋼鐵部分表面暴露于大氣環(huán)境中，此時鋅與鐵形成微電池，鋅的電位明顯低于鐵的電位，鋅則作為陽極對鋼鐵基板起到犧牲陽極的保護作用，防止鋼板的腐蝕發(fā)生。

After the coating damage, due to the sacrifice of corrosion, the steel base will also be protected, but if the damage reaches the steel base, the steel base is damaged, the sacrifice protection will be weakened, so the deeper damage must be rust prevention treatment (paint, etc.), to avoid further corrosion. In the protection of galvanizing layer is damaged, the surface of the steel part is exposed to the atmospheric environment, at this time, zinc and iron form micro batteries, the potential of zinc is significantly lower than that of iron, zinc as the anode to sacrifice the anode to protect the steel substrate, to prevent the corrosion of the steel plate.