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The story of titanium

construction-physics.com

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Re: The story of titanium

#181

Post by panick21_ »

bch wrote: post #45
petertodd wrote: post #25

Earlier quoted context omitted.

> We're not talking about exotic and expensive varieties of steel though. 4340 steel isn't exotic. It's one of the most commonly used grades of steel out there, and it's much cheaper than titanium. There are steels out there with significant stronger yield strengths too. Meanwhile the highest yield strength of any Ti alloy is Titanium is still a really great material in certain applications. But it's not magic. You h…

The family of materials we call steel is so fantastic, it almost a shame it’s so ubiquitous that we take it for granted. If it were invented today the front page of HN would be loaded with stories of this miracle material.

The newest generation most advanced spaceships are made from steel, see Starship.

When you go to both maximum cold (cryo fuel), and you go to maximum (reentry heat) then steel is amazing.

Aluminum would turn to butter on reentry, it would require a massive amount of heat shielding. Titanium alloys would have same issue.

Titanium alloy also become to brittle in deep cryo.

So steel beats everything in this demanding application. Its amazing.

Re: The story of titanium

#183

Post by rattray »

MeImCounting wrote: post #67
nico_h wrote: post #55

Earlier quoted context omitted.

It’s usually the frame and sides / scales that are made of titanium, never the blade afaik. Except maybe in some multitool keyring single piece doohickeys, but it’s not expected to cut anything beside the tape on your packaging.

Titanium so widely desirable for knife scales because of not only its strength to weight benefits but also interesting finishes that can be applied for instance anodization can give incredibly beautiful iridescent colors in a wide spectrum of potential colors and tones. I dont know how interested you are in modding your pocket knife but there are several very talented people that can do just stunning colorful and tex…

Where can I learn more about this?

Re: The story of titanium

#184

Post by jacquesm »

dreamcompiler wrote: post #131
cwillu wrote: post #119

Earlier quoted context omitted.

So called “mild steel” would be far more accurately called “iron”, the carbon content is insignificant.

The carbon content of mild steel is low but not insignificant. Pure wrought iron [0] is a dream to forge and it has a huge grain structure. It's more ductile than mild steel but it's also not as hardenable or tough as mild steel [1]. That little bit of carbon in mild steel makes a big difference. [0] I mean real wrought iron -- the almost 100% elemental stuff -- like the Eiffel tower is made of. This is practically u…

Wrought iron and mild steel are more or less functionally equivalent. One other reason why cast iron is so brittle is because it contains quite a bit of silicon.

Re: The story of titanium

#185

Post by drcongo »

hypercube33 wrote: post #168
drcongo wrote: post #53

Earlier quoted context omitted.

I have a nickel allergy so titanium is my first port of call for jewellery, though my wedding ring is zirconium and some of my old, pre-allergy stuff is now plated with rhodium.

niobium is a happy metal for nickel allergies. feels like tanium and doesn't trigger allergies. Source - my wife breaks out from nickel in jean rivets but niobium is good enough for piercings

Useful info, thanks!

Re: The story of titanium

#186

Post by 303uru »

kylehotchkiss wrote: post #32
303uru wrote: post #12

Love titanium, something so cool about it. It’s like steel with no downsides. I’ve got 5 ti bikes and a few ti watches, one of my favorite pieces though is my snow peak double wall titanium mug.

Do your bikes have carbon forks or TI? when I looked at TI bikes for fun in the past, the carbon forks surprised me, seemed like that should have been titanium too. How has your mug held up? Has it been compatibly durable compared to steel vacuum mugs? Snow peak makes great products but leans more lightweight than durable from my experience with their dishware

One does actually (https://bearclawbicycleco.com/titanium-gravel-fork/). Mug looks practically brand new several years later.

Re: The story of titanium

#187

Post by mhb »

BobaFloutist wrote: post #162
londons_explore wrote: post #28

Earlier quoted context omitted.

If you can 3D print titanium, then you can make a honeycomb structure overcoming this problem.

Can you 3D print metals yet? That sounds quite difficult.

Prototyping - Metal 3D Printing - Dan Gelbart

https://youtu.be/nyYcomX7Lus?si=E-B5VkFeX9W0Twc4

Re: The story of titanium

#188

Post by phenol »

cphajduk wrote: post #81
A_D_E_P_T wrote: post #63

Almost everything about the article is wrong, oversimplified, or misleading. Take this paragraph, for instance: > But despite its abundance, it's only recently that civilization has been able to use titanium as a metal (titanium dioxide has been in use somewhat longer as a paint pigment). Because titanium so readily bonds with oxygen and other elements, it doesn’t occur at all in metallic form in nature. One engineer…

The article may be an oversimplification, but your comment is an equal oversimplification. There are many environmental conditions that need to be assumed when comparing reactivity. For instance, if you have pure Titanium, pure Magnesium, pure aluminum in a vacuum at room temperature and proceed to introduce oxygen, you get the following reactions (simplified elemental chemical reactions, the Enthalpy of formation is…

to make a fair comparison here, you need to normalize per mole of metal. these enthalpies of formation are reported per mole of oxide, but there's twice as much Al per mole of Al2O3 than Ti in TiO2.
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