佛山镀锌钢带佛山镀锌钢带 SGCC镀锌板卷会生锈吗？

镀锌板卷会生锈吗？

Will the galvanized sheet roll rust?

那要看表面受损的程度，如果只是轻微的磨损，不会造成太大的影响，如果磨损较为严重露出了里面的钢材，那么就可能会引起生锈的情况。所谓不会生锈就是具有大气耐腐蚀性。

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.

为什么镀锌钢板具有耐腐蚀性？

Why does galvanized steel plate have corrosion resistance?

1）镀锌以后镀层是完好的

1) The coating is intact after galvanizing

由于锌将空气与钢基隔绝了开来，只发生锌的腐蚀，由于锌腐蚀的产物对锌有较好的保护作用，所以腐蚀速度非常慢，寿命是未镀锌钢板的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)的大气环境下， 钢板镀锌层经腐蚀后形成的浊产物为非溶性化合物(氢氧化锌、氧化锌和碳酸锌)，这些产物将以沉淀形式析出，形成致密的薄层，一般可达8µm厚度。这种薄膜既有一定厚度又不容易溶解于水，附着性又很强，因此它能起到隔离大气和镀锌板的屏障作用，防止腐蚀进一步发展。

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）如果锌层被被破坏了，牺牲腐蚀作用

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

镀层中的锌与钢带中的铁在潮湿的环境中组成了原电池，由于锌的标准电极电位只有-1.05V，低于铁的-0.036V，因而锌作为阳极被氧化，而铁作为阴极得到保护。由于锌腐蚀以后的生成物很致密，反应速度很慢，也就是说总体的耐腐蚀性能大幅度提高。这种防腐方法叫牺牲防腐。

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.

镀层损伤后，由于牺牲腐蚀作用，钢基同样也会得到保护，但是如果损伤达到钢基，钢基受损后，牺牲保护作用将变弱，所以较深的损伤一定要进行防锈处理（涂漆等），避免进一步锈蚀。在保护镀锌层遭到破坏，钢铁部分表面暴露于大气环境中，此时锌与铁形成微电池，锌的电位明显低于铁的电位，锌则作为阳极对钢铁基板起到牺牲阳极的保护作用，防止钢板的腐蚀发生。

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.