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The skeleton of the average skyscraper is steel. While it does have its advantages, they tend to get outweighed by two specific faults. One is a resistance to corrosion so poor that in a Life After People, it might stand firm for only 150 years. The other is that it's too heavy. So much, in fact, that nothing could get taller than the ridiculously narrow Burj Khalifa in Dubai.

So, for a taller building or other manmade structure, are there any metals or alloys tougher but lighter and thus longer-lasting than steel? If yes, then which?

What about glass? We've come to a point where scientists have created a glass as tough, if not more so, than steel. Could a glass skeleton be a public reality in the foreseeable future?

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    $\begingroup$ Titanium would be an option or stainless steel, the latter is used in architecture. $\endgroup$ – John Jan 10 '16 at 23:37
  • $\begingroup$ They build skyscrapers with stainless steel? $\endgroup$ – JohnWDailey Jan 10 '16 at 23:39
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    $\begingroup$ tough has a specific meaning in materials engineering. Being tough is not the only thing you need; e.g. tensile strength and hardness are different. See here foe a quick chart. Rubber is "toughest" for example but unsuitable for a tower! $\endgroup$ – JDługosz Jan 11 '16 at 2:09
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    $\begingroup$ Is money an object? There are many exotic materials which woudl be better, but are prohibitively expensive. $\endgroup$ – Cort Ammon Jan 11 '16 at 3:36
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    $\begingroup$ @HenryTaylor Ever tried building a skyscraper from rope? Nanotubes are awesome in tensile applications, but skyscraper also needs a material that holds well under compression and torsion. Great for space elevators, not so good for ground buildings. Also, their temperature stability only goes up to about 750 °C - far enough above room temperature, but a significant fire hazard. A simple candle flame can easily reach temperatures of 1 400 °C or so. Funnily enough, due to the interesting properties of CNTs, a camera flash can set them on fire. $\endgroup$ – Luaan Apr 11 '16 at 8:14
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Not yet, but maybe in the future.

There are a number of attributes that make materials desirable in constructing buildings. There are also various different ways to measure strength.

Steel has been and will remain the dominant construction framework material for the near future because it has high strength, reasonable anti-corrosion characteristics (when properly managed), and low cost. Steel has high strength in terms of both compression strength and yield strength, both are important.

What about alternatives?

Aluminum. Although stronger on a per mass basis, it is not as strong on a volumetric basis. A rule of thumb is that steel is twice as strong as aluminum, but aluminum only weighs about 1/3 as much as steel - both are available of alloys of different strengths. Aluminum also fails under cyclic loads and is more brittle (breaks at around 3% yield vs 20% yield for steel). Aluminum has an additional unsatisfactory problem for construction though, typical alloys lose much of their strength at 400 degrees F. This is simply a fatal flaw for building construction.

Titanium: Stronger per unit mass, but more expensive and considerably harder to work. Although abundant in the crust, much less than a million tons annual world production vs. over a billion tons for steel (about 10000:1 ratio overall). Does not have the high temperature strength of steel, but is better than aluminum. Titanium is very reactive, it will even burn in a burn nitrogen atmosphere. Titanium is popular where lightness and strength are dominant goals, such as fighter jets, but simply too expensive to use for building framing.

Superglass: Currently the superglass materials you refer to depend upon palladium. Palladium is expensive - today price 495.40 USD per ounce, 15,927 per kg. This glass will never be cheap enough for building construction unless the palladium can be replaced by something quite a bit cheaper. At which point, it may in fact become a common building material over time.

This superglass is not the same glass that we are all familiar with. The palladium allows the glass to be tough (bend without breaking) and retain its traditional strength. Some glass loses strength rapidly as temperature increases, other glasses actually get stronger for modest temperature increases. Without knowing the details for superglass, I can't guess this aspect and could not find any published detail related to strength at high temperature.

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    $\begingroup$ Love to see a link for superglass. $\endgroup$ – JDługosz Jan 11 '16 at 2:06
  • $\begingroup$ @JDługosz - search for the term "strongest glass" or "glass stronger than steel" you will find articles, many dating back to 2011 when it was first announced. $\endgroup$ – Gary Walker Jan 11 '16 at 2:16
  • $\begingroup$ lol superglass.de/startseite.html?&no_cache=1 $\endgroup$ – Sempie Jan 11 '16 at 14:14

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