Cheap Alternatives to Galvanizing Sheet Steel? 3

[mxracer17788]

Is anyone aware of any cheap alternatives to galvanized sheet steel? Normally we use a G90 gauge 12 steel, but we are trying to diversify our product line by offering a more corrosion resistant product for fairly cheap. Is there an alternative to galvanizing that will offer greater corrosion protection that is also affordable? Ideally, we would like to have the large coils of steel pre-coated before they arrived. I'm just looking for ideas here so start doing some research so anything would be helpful.

Thanks,
Jeff

 

[NickE]

In a word, no, if something provided better corrosion resistance at a lower cost than HDG, it would be used.

Nick

 

[mxracer17788]

I'm not looking for lower, just something on the same order of magnitude. More expensive is fine, just as long as it's reasonable. I'm looking for something to provide better corrosion resistance for a slight increase in price (but still less than stainless).

 

[TVP]

Have you investigated zinc-iron, zinc-nickel, or zinc-aluminum coatings? These are continuously applied, either by the hot-dip process, or by electrolytic processes. Steel coils can also be purchased with pre-applied organic coatings (paint), that can be decorative, corrosion resistant, etc. Some coil products have both coatings.

 

[mcgyvr]

and what do you do with the edges/exposed base metal after fabrication of this sheet?

How about galvannealed coils?

 

[vthomidis]

I would also think Zn-Fe ( i.e.type GALVALIA ) or Zn - Al ( GALFAN - ALUZINC ) as interesting alternatives.

They provide better corrosion protection and better colour adhension ( if so is required in your case ) than HDG.

Their prices are not signicantly higher than HDG and are available in coils and/or sheets.

 

[TomDOT]

Greater corrosion protection at a moderate increase in price? G120, or G210 galvanized sheet are the obvious answers.

Corrosion protection is directly related to the thickness of the galvanizing. Thicker galvanizing = greater corrosion protection.

 

[mxracer17788]

I am thinking about requesting samples for ZAM coating (

http://www.zam.biz/en/download/pdf/zam_02.pdf).

Does anyone have experience with this type of corrosion resistant coating? They claim that it is 10-20 times better in accelerated testing conditions than galvanized sheet steel, but you never know...

 

[mxracer17788]

Also TomDOT mentioned a thicker coating such as G210, but we would like to explore different options other than galvanization for diversified marketing purposes

 

[TomDOT]

mx,

Galvanizing is particularly weak in continuous-wet conditions, like most accelerated weathering. The zinc relies on forming a carbonate patina to slow corrosion - in continuous wet, you end up with more hydroxides, which are more soluble.

This makes any advertising comparisons using accelerated weathering extremely suspect. The ASTM B117 salt fog is particularly bad. Galvanizing which would last 40 years in normal outdoor conditions is likely to be gone in 1000 hours of B117.