I am looking for replacement steel for A588, ref support bracket

[daewoo]

I wish to have a bracket made, the steel on the dwg is A588 but my vendor is asking to use Steel A572 Gr.C Type 2 instead.
The part to be made is a 1/4 thick right angle bracket with a couple of mounting flanges welded to it with 1/2" dia holes.
Application t support motor in open salty enviroment.

Need toselect steel for strength / durability and corrosion

 

[ajh1]

Strength-wise A572 Grade 50 would seem to match up pretty well. I'm not sure what A572 Grade C is, possibly an old designation but no longer in the standard.
A588 is indicated to have better corrosion resistance than carbon steel (which A572 is closer to) so you might have a problem there. You could consider having the assembled bracket hot-dip galvanized for better corrosion resistance.

 

[metengr]

The ASTM A588 is a high strength, low alloy structural steel, similar to Mayari-50
with better atmospheric corrosion resistance than Corten plate. I would presume you had A588 Grade B material. The proposed alternative material is a high strength, low alloy vanadium-bearing structural steel (specified as Type 2).

The A 572 Grade should be specified as 50 Ksi or 55 Ksi to match the A 588 yield point specification of 50 Ksi min. unfortunately, the corrosion resistance of the A 572 material is lower than A 588 material. After fabrication of the bracket, I would consider hot dip galvanizing to provide for corrosion resistance.