Would exposed steel in a fire gain weight?

[BenBurch]

In my experiences in the steel mill, I observed the heavy body of scale that would have to be beaten off slabs about to enter the hot strip mill.

I wonder if a fire like WTC where exposed steel was allowed to get heated to deformation temperatures and held there for some time would allow the formation of enough scale to add significant weight to the structure?

Scale, of course, is metal oxide, and the weight gain is all of the oxygen that was picked up by the metals.

[leftysergeant]

Scale, of course, is metal oxide, and the weight gain is all of the oxygen that was picked up by the metals.

It seems to me that it would have to be heated to pretty near the melting temperature.

Further, it would have been obvious to even the causal observer at some point and would have been recorded, perhaps even included in the Hangar 17 collection right beside the meteor as an oddity of some note and import.

[peteweaver]

Metal oxide is the least of your worries when steel gets hot.

The loss of tensile strength and the tendency to creep, is far far more concerning.

I don't think it would gain much weight, but it would become much harder for it to support the loads acting on it.

[Architect]

I was unaware of any significant weight gain, and agree that compromising loadbearing ability through loss of strength is the key issue.