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The story of titanium

construction-physics.com

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Re: The story of titanium

#111

Post by ipv6ipv4 »

kylehotchkiss wrote: post #107
q7xvh97o2pDhNrh wrote: post #74

Earlier quoted context omitted.

Do you mind sharing where you got the titanium keyrings and carabiners? I've been searching forever for decent keyrings. There's a few carabiners (though the titanium ones are hard to find there too, and usually covered in obnoxious branding). But keyrings especially seem to be an under-served market. There's either (1) the usual mass-produced, flimsy, cheap garbage, or (2) something tougher and more expensive, but c…

Yes! I ordered these: https://www.amazon.com/Outus-Titanium-Rings-Split-Pack/dp/B0... My super-scientific "is titanium" test involved trying to get a fridge magnet to stick to them. it won't, and a normal keyring will. Yes, that risks it being aluminum. Other reviews state they put one against their sanding machine and got white sparks which was an additional positive sign. If you want to confidently get titanium, th…

Titanium anodizes very easily with a 9V battery and a wet paper towel. It’s a quick, and easy to way to test for titanium.

Re: The story of titanium

#112

Post by askvictor »

kylehotchkiss wrote: post #30
scrlk wrote: post #11

I can't help but recall Steve Jobs introducing the PowerBook G4 Titanium: > "Titanium! It's made out of titanium! Like the spy planes! This is an incredible material, it's stronger than steel yet lighter than aluminium." https://youtu.be/bNHkrnU77m0?t=92

I could see a day when titanium laptops return. Apple has invested in the some of the best mass machining in the world. I wonder what it’d look like sandblasted like their laptops and with their new coatings.

Wasn't one of the major problems that Titanium doesn't play well with Wifi? The TiBook predated built-in wifi, and I thought one of the reason to shift to Aluminum was wifi performance.

Re: The story of titanium

#113

Post by rendaw »

> After the war, the Bureau’s work on titanium accelerated. By 1947 it had successfully scaled up Kroll’s process

The article so far can be summarized as "people played around with titanium, but had no idea what to use it for" so why is the bureau suddenly trying to scale up production, or even mass producing it in the first place? It wasn't until 1948 that they identified engineering applications.

Re: The story of titanium

#114

Post by speed_spread »

jabl wrote: post #49
myself248 wrote: post #9

Earlier quoted context omitted.

Decades ago, Sears sold magnesium stepladders. I've used one, and it's freakishly light, a 6-foot step ladder that you can walk around with balanced on one finger. I've always wondered what a titanium one would be like.

> Decades ago, Sears sold magnesium stepladders. I've used one, and it's freakishly light, a 6-foot step ladder that you can walk around with balanced on one finger. As a slight aside, magnesium is also a very interesting material. It might be we're on the cusp of a major expansion in magnesium usage due to recent advancements - Mining from seawater (about 1 kg Mg in 1000L of seawater), or existing brine tailings fro…

Magnesium from mine tailings https://anrweb.vt.gov/PubDocs/DEC/GEO/TechReports/VGTR1998-1...

Re: The story of titanium

#115

Post by stevenwoo »

kylehotchkiss wrote: post #108
stevenwoo wrote: post #90

Earlier quoted context omitted.

Titanium needs to be in a bigger tube with thinner walls to take advantage of the properties compared to steel - the very first titanium bicycles used the available surplus tubing from defense/aeronautics industry that was close to steel bicycle tubing size and were notably not great until they used slightly bigger tubing and better titanium alloys. Forks have a couple of design features that make it hard to work wit…

This is super cool, I didn't realize the reason would be so complex. Thanks for explaining!

It's been done but the cost is very high compared to other materials because of the amount of specialized labor and only boutique builders offer one, the legs are really fat so it has poor aerodynamics so it's only suitable for off-road as a drop in replacement for a bicycle frame built for a suspension fork to account for the crown to tire distance and almost everyone has switched to suspension off-road. I've ridden some of the cheaper titanium forks and they flexed so much I did not feel comfortable riding them but have heard even the expensive ones flex quite a bit.

Re: The story of titanium

#116

Post by bch »

lmm wrote: post #105
bch wrote: post #40

Earlier quoted context omitted.

What is the response to stress by this build method? Will it fail gracefully over a lifetime of stresses? Any single big stress-event? In terms of (rigid, diamond-frame) bicycles, this is why I’m still firmly in the steel camp. No aluminium, no carbon; just steel. It really does have an excellent combination of nice ride quality, low weight, high strength, good failure mode (I’ve broken a few frames, and they tend to…

> In terms of (rigid, diamond-frame) bicycles, this is why I’m still firmly in the steel camp. No aluminium, no carbon; just steel. It really does have an excellent combination of nice ride quality, low weight, high strength, good failure mode (I’ve broken a few frames, and they tend to just bend/sag, vs the rapid unscheduled disassembling of carbon/Al). Bicycles don't have the minimum size problem GGP is talking abo…

> Bicycles don't have the minimum size problem GGP is talking about

Good point.

> Titanium is pretty much the perfect frame material[…]

Anecdotally - I understand it’s tougher to work with at about every single step. I’ve seen too many cracked Ti bikes/parts to sign up, I think. I understand the lust though.

Re: The story of titanium

#117

Post by pests »

Turing_Machine wrote: post #27
danielodievich wrote: post #3

As a kid in my father's workshop we had several 4mm thick titanium plates, scavenged from some industrial stuff in USSR research facility nearby. I had a lot of fun getting my visiting friends tey to dent it with hammers. No matter how hard you struck it just didn't care. Only the oxidation patina would show some trace of impact. It was absolute magic to me. And so incredibly light!

The article mentions that the Soviet Union had lots of titanium ore, and also that it was heavily used in the A-12/SR-71 family of aircraft. I remember reading elsewhere that the CIA set up a bunch of front operations across the world to buy titanium (or maybe titanium ore) from the USSR without them finding out what it was being used for. They didn't want the "Ship to:" part of the order form reading "Lockheed Skunk…

Elsewhere would of course be the excellent "Skunk Works: A Personal Memoir of My Years at Lockheed" by Ben Rich.

Highly reccomended and goes into further engineering and design challenges of the RS-71 Blackbird and its titanium construction.

Re: The story of titanium

#118

Post by gnarcoregrizz »

megraf wrote: post #19

Resting next to me is a titanium ring, it is extremely light, resistant to ambient temp change, and is usually cool to the touch. It cost $15 or so. It wears in a really beautiful way, aging like it's enjoying itself. On my finger is a tungsten carbide ring, it's extremely dense (that of gold, slightly heavier than uranium), and has a lot of interesting properties. It's warmed quickly by my fingers, and rings the mos…

I have one too. It’s not my favorite to wear because it has zero heft. It’s unsubstantial and has a strange plasticky somewhat sticky feel. I plan on replacing it with gold. I can’t complain about the price though - they came in a box of 3.

Re: The story of titanium

#119

Post by cwillu »

saberience wrote: post #22
AlotOfReading wrote: post #20

Earlier quoted context omitted.

Steel's strength varies by orders of magnitude depending on the alloy and heat treatment. It's an incredibly flexible family of materials. Some members of that family are far stronger than anything in the titanium family, e.g. 4340 steel has a nominal yield strength of >1800 MPa, compared to <1300 MPa for Ti 10-2-3.

We're not talking about exotic and expensive varieties of steel though. We're just talking about "general" or common steel and comparing it to unalloyed "common"/"general" titanium. Remember, Steel is itself an alloy, Titanium is an element. If you start comparing Titanium alloys to Steel then the comparison gets even harder. Titanium alloys are in general stronger than steel as well as much lighter and more corrosio…

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

Re: The story of titanium

#120

Post by tuatoru »

avs733 wrote: post #10
hef19898 wrote: post #8

Earlier quoted context omitted.

Damn, imagine having a titanium shovel! I want one!

https://nearzero.co/products/shovel They exist! Meant for backpacking/back country work. I spent a summer as a wilderness search and rescue intern/volunteer/grunt/mule during college and was shocked at how much weight could have been saved with better gear. There’s just a minimal market for it.

Oh, there's a market for lightweight backpacking gear, all right! Check out Backpacking Light for in-depth reviews.

Garage Grown Gear has some of the trendy light and ultralight stuff.

1. https://backpackinglight.com/

2. https://www.garagegrowngear.com/

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