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The story of titanium

construction-physics.com

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Re: The story of titanium

#21

Post by petertodd »

saberience wrote: post #16
petertodd wrote: post #13

Earlier quoted context omitted.

Those must have been soft hammers. Titanium isn't magic. It's neither as hard, nor as strong, as steel. It's a lot lighter, which makes it a wonder material in certain applications that can take advantage of it's excellent strength-to-weight ratio. But if max hardness, or strength at a given size, is what you are after, without a weight constraint, steel wins.

I mean, I'm no materials scientist but one google tells me that Titanium is AS strong as steel but much less dense. I just browsed through the top 10 Google results and everyone states that titanium is roughly equal to steel in strength but with various other benefits. So your comment is definitely off-base somewhere, you make it seem like steel is much stronger, which clearly isn't the case.

Read this for starters: https://www.thomasnet.com/articles/metals-metal-products/ste...

"When comparing the tensile yield strengths of titanium and steel, an interesting fact occurs; steel is by-and-large stronger than titanium."

Many people confuse this issue, because they're actually talking about measures of strength/weight ratios, on which titanium does really well. But if you are size limited rather than weight limited, steel is often a better material than titanium even when cost is no object.

Re: The story of titanium

#22

Post by saberience »

AlotOfReading wrote: post #20
saberience wrote: post #16

Earlier quoted context omitted.

I mean, I'm no materials scientist but one google tells me that Titanium is AS strong as steel but much less dense. I just browsed through the top 10 Google results and everyone states that titanium is roughly equal to steel in strength but with various other benefits. So your comment is definitely off-base somewhere, you make it seem like steel is much stronger, which clearly isn't the case.

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 corrosion resistant.

Re: The story of titanium

#23

Post by saberience »

petertodd wrote: post #21
saberience wrote: post #16

Earlier quoted context omitted.

I mean, I'm no materials scientist but one google tells me that Titanium is AS strong as steel but much less dense. I just browsed through the top 10 Google results and everyone states that titanium is roughly equal to steel in strength but with various other benefits. So your comment is definitely off-base somewhere, you make it seem like steel is much stronger, which clearly isn't the case.

Read this for starters: https://www.thomasnet.com/articles/metals-metal-products/ste... "When comparing the tensile yield strengths of titanium and steel, an interesting fact occurs; steel is by-and-large stronger than titanium." Many people confuse this issue, because they're actually talking about measures of strength/weight ratios, on which titanium does really well. But if you are size limited rather than weight…

Every source says that titanium is as strong as the most commonly used steel. Sure if you're going for lesser used alloys of steel you may as well compare to lesser used alloys of titanium. Or just compare iron with titanium, as that's really comparing one element with another, and is the "fair" comparison.

And anyway, your original comment suggested someone was totally in the wrong for thinking a 4mm titanium plate was strong, which is obviously incorrect. 4mmm of titanium plate is clearly going to be really strong and resistant. They wouldn't make plane engines from it if it wasn't.

Re: The story of titanium

#25

Post by petertodd »

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…

> 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 have to use it intelligently in the right application to get a benefit from it.

Re: The story of titanium

#26

Post by Ingaz »

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 had IBM notebook with titanium case (before it became Lenovo)

Re: The story of titanium

#27

Post by Turing_Machine »

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 Skunkworks, Burbank Califoria". Heh.

Re: The story of titanium

#28

Post by londons_explore »

petertodd wrote: post #15
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.

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.

Re: The story of titanium

#29

Post by kylehotchkiss »

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 wear a titanium ring too and keep my real one safely locked away. It’s an incredible metal that I proudly wear around. Mine cost about the same.

I also have a titanium pocketknife (James Brand), carabiner, keyrings, pens, camera (fujifilm makes a few), and some beloved snow peak dishes. And the silly titanium iPhone. It’s such a great metal to make things to carry with.

Re: The story of titanium

#30

Post by kylehotchkiss »

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.
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