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The story of titanium

construction-physics.com

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Re: The story of titanium

#161

Post by sufficer »

dredmorbius wrote: post #156
TylerE wrote: post #135

Earlier quoted context omitted.

This is also why aircraft use aluminum, despite the major downsides (finite fatigue life, mainly). There’s just no way steel would work (far too heavy). Titanium is awesome but a royal pain to work with. Carbon fiber is starting to come in but it has issues to - although they’ll be overcome with time.

The Soviet Mikoyan-Gurevich MiG-25 was manufactured principally from stainless steel. The result was a stunningly fast fighter aircraft, capable of Mach 3.2, though in practice engine overheating restricted operation maximum to Mach 2.83 (3,000 km/h), and even that for only 5 minutes at a time as the airframe and fuel would overheat. The MiG-25's mass necessitated huge wings (and overall dimensions), and limited mane…

This aircraft also sparked development of the F15 which was superior to anything soviet for 10+ years

Re: The story of titanium

#162

Post by BobaFloutist »

londons_explore wrote: post #28
petertodd wrote: post #15

Earlier quoted context omitted.

A lot heavier actually. In an application like a stepladder, you have to work with certain minimum dimensions for the stepladder to be practical (eg rungs and sides have to fit in the hands nicely). You also have to have certain minimum thicknesses on the parts to have sufficient resistance to local deformation (eg dropping a hammer on the rungs). That forces the parts to be significantly larger and stronger than the…

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.

Re: The story of titanium

#163

Post by vGPU »

sufficer wrote: post #161
dredmorbius wrote: post #156

Earlier quoted context omitted.

The Soviet Mikoyan-Gurevich MiG-25 was manufactured principally from stainless steel. The result was a stunningly fast fighter aircraft, capable of Mach 3.2, though in practice engine overheating restricted operation maximum to Mach 2.83 (3,000 km/h), and even that for only 5 minutes at a time as the airframe and fuel would overheat. The MiG-25's mass necessitated huge wings (and overall dimensions), and limited mane…

This aircraft also sparked development of the F15 which was superior to anything soviet for 10+ years

Sure but the f15 didn’t start production until almost a decade later.

Re: The story of titanium

#164

Post by blincoln »

scythe wrote: post #155
MeImCounting wrote: post #70

Earlier quoted context omitted.

Thats cool! I didnt know there were specific common applications where grade 1 would be desirable compared to the stronger alloys available.

IIRC you can buy titanium foil that you can just make stuff out of at home.

I have some titanium crafting wire. Should be easy to find on Amazon or similar. It's a little surreal - looks similar to a roll of steel wire, but feels as lightweight as PLA. Basically the real-world version of mithril.

Re: The story of titanium

#165

Post by cyberax »

dreamcompiler wrote: post #129
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.

Magnesium stepladders are great until one catches on fire because you try to weld something onto it or get it too close to a welding torch. Then things get spicy.

Huh. Now I want to buy a magnesium ladder and set it on fire.

Re: The story of titanium

#166

Post by Skunkleton »

SV_BubbleTime wrote: post #159
Skunkleton wrote: post #133

Earlier quoted context omitted.

The iPhone 15 pro is mostly aluminum. There is about a 1mm thick band of titanium around an aluminum frame. https://www.apple.com/newsroom/2023/09/apple-unveils-iphone-... https://www.youtube.com/watch?v=S_W73ouKtjU&t=605s

And that makes perfect sense. Thick walls on the iPhone are what are going to prevent X Y area which I suspect they need more than thickness.

Seems like marketing to me. They got rid of the stainless steel frame from previous models, switched back to aluminum, then added a pointless band of titanium so they could say Titanium in their marketing.

Re: The story of titanium

#167

Post by dreamcompiler »

cyberax wrote: post #165
dreamcompiler wrote: post #129

Earlier quoted context omitted.

Magnesium stepladders are great until one catches on fire because you try to weld something onto it or get it too close to a welding torch. Then things get spicy.

Huh. Now I want to buy a magnesium ladder and set it on fire.

If you do, take it out into the middle of nowhere first because you won't be able to put the fire out (unless you bring a Class D extinguisher--good luck finding one of those at your nearby hardware store). Don't put water on it because that just makes it burn hotter.

Re: The story of titanium

#168

Post by hypercube33 »

drcongo wrote: post #53
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 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

Re: The story of titanium

#169

Post by smazga »

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.

Sort of! https://thevirtualfoundry.com

Not directly extruding it, but the end result is metal.

Re: The story of titanium

#170

Post by justinator »

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…

I had to do a double take on your "about 1 kg Mg in 1000L of seawater" stat, thinking it was for titanium, rather than magnesium.

For those curious, titanium is present in sea water, at 1 ppb! (magnesium is 1300 ppm)

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