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by hdivider 938 days ago
Huge fan of Titanium.

If only we could find a cheap way to get the metal out of titanium dioxide. Like a Haber process-level breakthrough.

Then we could start replacing steel with titanium in many applications. Think entire freight trains, cargo ships, containers, cars, trucks, tractors -- all that heavy steel replaced by titanium alloys.

Enormous quantities of fuel and energy saved by lower density and higher strength. In many applications, it would likely make stainless steel obsolete.

Trillions of dollars of value may be locked up in such a breakthrough.

4 comments

I think it could be one of those 'grass-is-greener' scenarios. Steel is really nice to work with. It's strong and elastic and you can do all sorts of things to alter its properties, like even in a home shop.

Titanium always looks really hard to work with, just from the few times I've seen youtube types get some into their lathe chucks.

Would the added (in some ways just different) performance make up the difference? No idea. I mean, would people use so much aluminium if it wasn't straightforward to extrude it into interesting shapes? I don't think I would.

The straight characteristics of a material are one thing: what you can actually do with it are another.

https://en.wikipedia.org/wiki/Titanium_alloys

Looks like alloys are much more mallable, while losing almost none of the qualities of pure titanium.

Also: Go nukkular, high-temperature to be specific.

maybe if the blast furnace hadn't been invented nearly a thousand years ago we wouldn't be so familiar with the techniques that work well on steel
That's true. On the other hand, people have been working with flint for longer than there have been people, and it remains fiendishly hard to make anything with it.
that's maybe an exaggeration; people still make buildings out of flint, they make it into perfect spheres for ball mills, and when flintlock was the firing mechanism of choice, they shaped flints for rifles out of it. the main reason we don't have a lot of flint goods around is that, aside from its edge-forming powers, it doesn't have great properties: it's brittle, nonconductive and not all that pretty, much like unglazed fired clay

you can grind it into whatever shape you want if you're careful about silicosis

The ground is covered with flint arrowheads in various parts of TX that I’ve visited and/or inhabited. It’s really hard for me to imagine Indians crafting so many of them if it were that hard to work with.
They had no other viable options. It is hard to work with.
That's why I said titanium alloys specifically. With such a large-scale industrial transformation, definitely many alloys would be explored, to fit the needs of new industries. We don't use pure iron for any serious applications either.
Fatigue is why we use steel for everything, no other alloys have the practical strength and infinite life.
You are correct in that steel is harder and stiffer than titanium. Steel is also more re-usable, smelt-able than titanium.

However, when it comes to fatigue (which I assume, you are referring to fracture strain) titanium has a significant edge. The fracture strain for steel is roughly 15%, but for titanium alloys, it often reaches and exceeds 50%.

I don't say this to contradict you, but to point out that as with most things in life, "it depends".

Source: https://www.ulbrich.com/blog/titanium-versus-steel-a-battle-....

A better argument for steel is it requires 5-10 kwhr/kg to produce vs 60kwhr/kg for aluminum and 250kwhr/kg for titanium. So for the same energy you get 6 times more steel than aluminum and 25 times more than titanium. Which seems to say when the properties of steel are acceptable it's the cheaper option.

https://solar.lowtechmagazine.com/2009/06/how-much-energy-do...

Like steel, titanium alloys have a distinct non-zero fatigue limit, and thus can be engineered to have infinite fatigue lives. Though the exact details differ and steel or titanium can be better depending on exactly what the conditions are.
Metalysis have made claims like this: https://metalysis.com/

Based on this tech: https://en.m.wikipedia.org/wiki/FFC_Cambridge_process

Still waiting for my titanium girders though...

This is cool. Thanks!

In my mind, this is what real technology entrepreneurship looks like. As opposed to the latest crypto or social media thing.

> Then we could start replacing steel with titanium in many applications.

The world's production of stainless steel is growing almost exponentially and we are replacing many applications or ordinary steel with stainless. Every year millions of tons of steel are lost to rust.

Its a gigsntic shift noone is noticing