关于钢板表面热浸锌和钢板元素含量关系介绍（英文的）

daviddzj

We manufacture steel poles and outdoor sports lighting fixtures. We experienced the same thing you are experiencing about 1 year ago.
Our problems were either related to
a) high phosphorus content
or
9 R9 y- u  f( Yb) high silicon content.
. A$ `( a& k# M! EOur galvanizer first alerted us of the problem before the product had even made it out of their plant. They speculated what the problem was, but asked if they could keep a couple samples to have chemically analyzed to confirm for us. We agreed and sure enough they were right. To date, every time we've had problems with galvanizing this has been the problem.
Through a lot of headaches, we were able to work with them to define the chemical content of the steel. This information is available through the American Hot Dip Galvanizers Assoc. They can also give you information that I won't really go into (particularly since I'm no expert) to explain the effects of high silicon and/or high phosphorus. If you continue to pursue, you will likely find, as we did, that good galvanizing can be assured if the chemical content of the steel meets one of the 3 following criteria.
) m8 ]7 y* L; z/ C0 e1)
Carbon < or = .25%
" u! Z8 o8 u( ]- @2 hSilicon < or = .04%
7 ?" y, b% y3 V6 jPhos. < or = .02%
2)
1 [1 M  b) ^& E% YCarbon < or = .25%
6 [5 G( B$ g2 O5 X7 xSilicon between .15% and .20% {we've had success going as high as .25% on silicon with this criteria)
1 F6 [8 f0 j/ _& p: h/ O$ ~+ APhos. < or = .02%
! E7 c; O% _6 S. J: R, O. q' J, W& P3)
Carbon < or = .25%
Silicon + 2.5 (PHOS) < or = .09%
The farther you can stay below the upper limits the better your success will be. Also, you'll find that equation 2 primarily pertains to ASTM A36 material. Equation 3 will allow silicon or Phos to exceed the limit in equation 1, as long as the other decreases.
Lastly, when we added these specs to our prints our vendors' first reaction was that it would be more costly material. That has never really materialized. We do require mill certification now with all steel received that will be galvanized.

zincshine

相信樓主這裡說的是關於熱浸锌层表面出现局部发黑, 表面不平整等問題. 硅和磷含量过高一向是熱浸锌會遇到的問題, 尤其是在国內, 钢材材质普遍大量的以硅为脫氧劑, 導致钢材含硅量较其餘国家所生产的钢材为高. 致于应付硅和磷含量过高的問題, 可以在锌溶液中加入 nickel, 大概在 0.5% 以上, 就能有效压抑 锌鉄合金层增長過快的問題. 另外, 控制鍍鋅时間也能有效解決鋅層過厚的問題