Galvanic corrosion of similar-ish steels

• Aug 23, 2024

• #2

EdStainless

Materials

May 20, 2004

16,016

You are more likely to have galvanic issues just because of variations in surface condition on the same material.
Don't worry about this.

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P.E. Metallurgy, consulting work welcomed

 

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• Aug 23, 2024

• #3

TugboatEng

Marine/Ocean

Nov 1, 2015

11,461

I have found that the strength of the steel correlates to its sensitivity to galvanic corrosive. For example, 70ksi welds or 150ksi bolts tend to be anodic to A36 steel structures.

In open air you won't notice much but submerged in salt water there will be substantial galvanic corrosion effect.

 

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• Aug 24, 2024

• #4

stevenal

Electrical

Aug 20, 2001

3,798

My understanding is that molecules of the different alloys within the metal itself can form galvanic cells if exposed to electrolyte.

 

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• Aug 24, 2024

• #5

TugboatEng

Marine/Ocean

Nov 1, 2015

11,461

This is true for brass. In the case of brass it's called dezincification. I don't know of any other examples.

 

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• Aug 27, 2024

• #6

LittleWheels

Structural

Nov 27, 2001

337

Some types of cast iron are very subject to graphitic corrosion/ graphitization, a similar degradation mechanism to dezincification of brass.

 

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