镀锌件锌层破损，用环氧富锌底漆进行修补，在此处环氧富锌底漆的主要作用是屏蔽还是其中的锌粉的

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  laoc092013-06-02 12:19#2

      纯环氧就可以了。

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  larry2013-06-02 14:46#3

  topbobby:就涂层的作用来说，肯定是两个作用都有，但是谈到主要作用，我个人觉得应该是利用锌的阴极保护作用更多一点，如果单纯要barrier的作用，可以选用纯环氧，而之所以不选用无机锌，是因为修补工作，不可避免要有涂层的搭接，The patch of organic zinc-rich coating must extend a mi .. (2013-06-02 11:11) 

  某品牌涂料，环氧富锌的名称就叫Barrier，而无机锌才是起电化学保护的锌粉品种。

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  topbobby2013-06-02 16:19#4

  larry:某品牌涂料，环氧富锌的名称就叫Barrier，而无机锌才是起电化学保护的锌粉品种。 (2013-06-02 14:46)

   There are two requirements essential for effective operation of organic zinc-rich coatings:
  1. Zinc in the vehicle, in order to provide the cathodic protection required by zinc-rich coatings, must be in particle-to-particle contact or contain a conductive filler, such as iron phosphide, to make an electrically conductive path through the organic matrix. Without this particleto-particle contact, zinc in the coating essentially would be inert and surrounded by the organic vehicle,
  which would not allow the zinc to go into solution and provide the cathodic protection.
  2. The second important consideration in organic zinc-rich primers is that the vehicle or carrier of zinc pigment be alkali resistant. This is important since zinc, particularly under chloride environments, reacts to form a strong alkali that would adversely effect any alkali-sensitive resin or binder.The primary organic resins used to make organic zinc-rich primers are chlorinated
   rubbers, phenoxy resins, or catalyzed epoxy resins. While there are a number of other
  materials that can be used, these are the principal ones applied to steel structures.
  从第一条可以看出，Organic zinc-rich primer 是完全可以利用到锌的阴极保护作用的。
  还有一点，完整的涂层起到是barrier作用，而锌的作用是在涂层不在intact的状态，出现discontinuities的时候起作用的

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  chgzh01012013-06-02 21:32#5

  topbobby:There are two requirements essential for effective operation of organic zinc-rich coatings:
  1. Zinc in the vehicle, in order to provide the cathodic protection required by zinc-rich coatings, must be in particle-to-particle contact or contain a conductive fi .. (2013-06-02 16:19)

  larry说的是JOTUN的环氧富锌底漆。

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  chgzh01012013-06-02 21:57#6

  topbobby:就涂层的作用来说，肯定是两个作用都有，但是谈到主要作用，我个人觉得应该是利用锌的阴极保护作用更多一点，如果单纯要barrier的作用，可以选用纯环氧，而之所以不选用无机锌，是因为修补工作，不可避免要有涂层的搭接，The patch of organic zinc-rich coating must extend a mi .. (2013-06-02 11:11) 

  LZ说的是环氧富锌底漆。

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  chgzh01012013-06-02 21:58#7

  larry:某品牌涂料，环氧富锌的名称就叫Barrier，而无机锌才是起电化学保护的锌粉品种。 (2013-06-02 14:46) 

  无机锌和环氧富锌都可以起电化学保护作用。

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  topbobby2013-06-02 22:07#8

  chgzh0101:LZ说的是环氧富锌底漆。 (2013-06-02 21:57) 

  我说的也是环氧富锌底漆啊。。。不明白你表达的意思

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  chgzh01012013-06-02 22:15#9

  topbobby:我说的也是环氧富锌底漆啊。。。不明白你表达的意思 (2013-06-02 22:07)

  The patch of organic zinc-rich coating must extend a minimum of
  five centimeters (two inches) over the undamaged zinc coated surface.而type I无机锌不能施工于任何旧的涂层。
  
  英文部分为有机富锌涂层，中文的为无机锌，无机锌可以覆盖无机锌。

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  topbobby2013-06-03 07:44#10

  这个真是我孤陋寡闻了，我认为无机锌之间是不可以直接复涂的。

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  larry2013-06-03 10:17#11

  topbobby:这个真是我孤陋寡闻了，我认为无机锌之间是不可以直接复涂的。 (2013-06-03 07:44) 

  以前做舱盖的时候，都知道无机锌不可复涂，等到做过化学品舱室的时候，才知道有那么几家的无机锌是可以复涂的。

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  chgzh01012013-06-03 21:09#12

  larry:以前做舱盖的时候，都知道无机锌不可复涂，等到做过化学品舱室的时候，才知道有那么几家的无机锌是可以复涂的。 (2013-06-03 10:17) 

  还是larry兄见多识广。

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  ljchb2013-06-04 10:28#13

  环氧富锌是否有阴极保护作用，还是有争论。上CIP课的时候，老师说环氧富锌没有阴极保护作用。但是国内的教育、书籍、杂志等是认为环氧富锌有阴极保护作用的。

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  chgzh01012013-06-04 12:00#14

  ljchb:环氧富锌是否有阴极保护作用，还是有争论。上CIP课的时候，老师说环氧富锌没有阴极保护作用。但是国内的教育、书籍、杂志等是认为环氧富锌有阴极保护作用的。 (2013-06-04 10:28)

  Sacrificial coatings, which are rich in zinc. Whenever a scratch or other damage occurs to the zinc exposed to the steel, the zinc acts as a sacrificial anode and corrodes to protect the steel surface.
  
  以上内容是我从NACE CIP Level 1 Coating Inspector Program上摘录的内容，环氧富锌底漆有阴极保护的作用，至于你所说的存在争论，国外标准或文献资料上面有没有相关的信息，愿闻其详。

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  春雨弯刀2013-06-04 12:31#15

  chgzh0101:Sacrificial coatings, which are rich in zinc. Whenever a scratch or other damage occurs to the zinc exposed to the steel, the zinc acts as a sacrificial anode and corrodes to protect the steel surface.
  
  以上内容是我从NACE CIP Level 1 Coating Inspector Progra .. (2013-06-04 12:00) 

  我所查询的资料中也提到了
  
  The electrochemical protection provided to steel by zinc coatings is a vital element in the effectiveness of galvanized coatings in protecting steel from corrosion.
  
  While the potential difference between metals is the prime driving force providing the corrosion current, it is not a reliable guide to the rate and type of corrosion occurring at a particular point. The severity of galvanic corrosion also depends on the ratio of the areas of metals in contact, the duration of wetness (galvanic corrosion can only occur in the presence of a conductive solution) and the conductivity of the electrolyte. The presence of oxide films on the surface of one or both of the metals can greatly inhibit galvanic corrosion.

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  ljchb2013-06-04 12:50#16

  chgzh0101:Sacrificial coatings, which are rich in zinc. Whenever a scratch or other damage occurs to the zinc exposed to the steel, the zinc acts as a sacrificial anode and corrodes to protect the steel surface.
  
  以上内容是我从NACE CIP Level 1 Coating Inspector Progra .. (2013-06-04 12:00) 

  可是，上课时老师（老外）是这样讲的。

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  zinctop2013-06-05 09:08#17

  是否有阴极保护作用取决于所含锌粉能否形成桥接。有实验数据表明干膜内所含锌量超过92%才有可能形成桥接。
  要达到这么高的含锌量，对成膜物质的选用是十分挑剔的。

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