Theories behind thermal differences in Corrosion- Ideas

[Japsanity]

Hi there, first time posting.

 

When using an infrared camera on a corroded (heated to 100 degrees) steel beam with corrosion pits, the image shows a minor difference in temperature between corroded areas and non corroded areas.

The rust that developed was removed before the experiment.

 

I wanted to know the theory behind why corroded areas of steel show different thermal properties.

 

any ideas?

[studiot]

Interesting observation.

Welcome to Scienceforums.

 

Please fill in a few more details of the experiment.

 

Was the camera used on the beam at 100^oC

Why was the beam heated?

Was this done after the (surface) rust was removed?

Was the experiment continued long enough for the beam temperature to equalise?

 

 

Corrosion involves the establishment of chemically different zones on the surface and within the body of the material.

As the corrosion proceeds the material in these zones (called anodic and cathodic zones) changes chemical composition so the beam material is is no longer homogeneous.

I suspect that this has something to do with the phenomenon, but more details are needed please.