There has to be a better way to make titanium | Hacker News Reader

There has to be a better way to make titanium

orcasciences.com

40 pointsArmic13 comments

This is interesting. I questioned the "why is tinanium so expensive" more than once and the only answer was "It's hard to make"

I have a bit of a titanium fetish. 90% of my cutlery and cups in the kitchen are now made of titanium. I especially love the (double-walled) bowls.

I really like touching the material. I like its aesthetic. I find it very strange myself. My first encounter was 15 years ago with the Snow Peak spork that I bought for outdoor activities/camping. Later, I acquired a Snow Peak cup, which I still use every day.

Titanium is super easy to clean as well, without the downsides of non-stick surfaces. Silicone is the only other material that competes in my mind, although obviously it's used for different things than titanium.

As someone with a self proclaimed fetish I have to ask if you have ever tried working with the material? I find even the most basic manipulation to be wild compared to other common metals.

I was sanding and polishing a long handled titanium spoon to make it more smooth (slowly) by hand and the friction from that quickly made it too hot to hold. It's thermal conductivity is 1/10th of aluminum and roughly 1/2 of stainless steel.

Another fun thing is to anodize it to different colors. Compared to aluminum it can be achieved without the use of caustic chemicals.

The work hardening when machining titanium is also just brutal, worse than stainless

Wasn’t there also some issue with water when the A-12 or SR-71 was being built? Like the local water treatment plant started fluoridating the water or something, and it completely screwed up the production process?

"Completely screwed up the production process" seems a bit overstatement: with the budgets at stake for these projects, adding a distillation step to the water isn't some massive financial burden.

Fair enough! I think the primary issue was that for a while, no one had any idea why previous processes just stopped working. But my recollection of this is obviously hazy at best.

Yes. They had to scrap tons of parts until they figured it out.

iirc they had to add the impurity back IN to get the process working again.

Weirdest thing I know about titanium: it acts as a sponge for hydrogen, to the extent that H will knock Ti atoms out of the material until it becomes friable.

This is never observed in ordinary usage, because titanium dioxide forms SO DAMN QUICKLY, and completely blocks absorption of H.

Source: a series of failed parts inside a high vacuum device (chip photolitho).

This point was also briefly mentioned in the article, but I think is other half of the equation: even if Ti is made cheap to manufacture, it's use will still remain problematic as it's brutal to machine and form, which increases manufacturing costs drastically.

I wonder if research into magnesium alloys would be a more fruitful avenue for research.

Is it cost effective to go from sponge to powder then Electron Beam Melting?

TLDR, AFAICT:

A: refining the titanium is probably fairly close to maximally efficient. But converting the refined titanium sponge into the final product has a ton of steps, and figuring out ways to delete one or two of those steps would pay dividends.

B: Assuming that the price of energy is going to drop relative to the other costs in the process is probably a safe assumption that can be exploited.

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