Good From Bad: Steel in the Towers to Steel in Fusion Reactors
Sep 11th, 2008 | By Jonathan Golob | Category: Lit Round-upVia the BBC:
Scientists say an understanding of how the Twin Towers collapsed will help them develop the materials needed to build fusion reactors.
New research shows how steel will fail at high temperatures because of the magnetic properties of the metal…
The key advance is the understanding that, at high temperatures, tiny irregularities in a steel’s structure can disrupt its internal magnetic fields, making the rigid metal soft.
“Steels melt at about 1,150C (2,102F), but lose strength at much lower temperatures,” explained Dr Sergei Dudarev, principal scientist at the United Kingdom Atomic Energy Authority (UKAEA).
At room temperature, the magnetic fields between iron atoms remain regular, but when heated, these fields are altered allowing the atoms to slide past each other, weakening the steel….
The peak in this pliability is at 911.5C, but begins at much lower temperatures, at around 500C (932F) – a temperature often reached during building fires.
The steel backbone of the Twin Towers was probably exposed to temperatures close to this, when insulating panels – meant to protect the buildings’ structural frame – were dislodged by the impacts of the hijacked planes.
Part of the mysteries of the falling towers has to do with the extremity of the situation. Steel really hadn’t been placed into such a situation–with both intense heat and enormous stress and strain–before the towers fell. We learned something about our world that we can now apply to the future.