A mate had titanium screws from an F-111 engine.
About 1/4'" diameter and 12" long they sure were not soft or bendy.
The ringing caused when tapping on the edge of a bench just about broke fingers.
Dan.
I have a handful in my ankle. Not easily accessible. They are expensive (medical so they have to be) but titanium seems to be prefered for holding bones together.
In my space days beryllium was prized for use in the oddly named BAPTA (bearing and power transfer assembly) in 3 axis stabilised satellites. Basically the bit that holds the solar panels on and lets them turn to face the sun. From a tribology perspective Be was the dogs danglies. Someone had to machine it from solid blocks. Never saw where they hit that on site but was told vast volumes of coolant were used as a Be swarf fire is a very bad thing (tm).
I had a noise abatement client a ways back. They ground magnesium ingots into powder. Three bunker isolated units. When things went off it was BOOM. They had a hinged wall that would flip up to let it all out. Replace the burned stuff and back to business.
Beryllium is very toxic. Same for beryllium oxide. Cutting grinding and dealing with swarf should not be taken lightly. Probably that factory is no a healthy place to be. Back in the 1970's I heard stories about machinists who did not take the warning seriously. They weren't around any more.
Materion https://materion.com/ The only real supplier of BE diaphragms in the world, has done a lot to protect those who work around the stuff. You don't even want a cut from the stuff. The Asia stuff is vacuum deposited and I'm not sure it does much acoustically, used that way.
😱 Jeesh - think I'll stick to my silk domes, thanks. In later years I'm inclined to think the waveguide is more important anyway (beyond a certain point at least).
The only real advantage of the vapor deposition over the foil Be from Materion is that the vapor deposition can be lighter, less mass than is possible with the foil. On the other hand the way the structure is formed in the vapor deposition process this creates a weaker structure as far as fracturing compared to the foil and structural failure would be much more common with the vapor depo parts. Vapor deposition is an expensive process and is rather slow compared to forming with foil. I was told the secret to making the foil diaphragms possible without fracturing is heat, the foil is heated before forming to make the foil more pliable when pressing the shapes. Otherwise the depth of curvature that was possible was not enough to work for a diaphragm, this was the trick that Materion/Brush Wellman had to work out. The Be foil is much less likely than a vapor deposition to give off small particles if broken, it is much safer for the use in audio loudspeakers.
Bone grafts to titanium pretty well, so it's considered a "permanent" installation. My mom has Ti hardware in her ankle as well.
I have stainless screws and plate in my clavicle because that hardware is often removed after the bone re-fuses and my surgeon wanted as thin a plate as possible for the location.
Have we looped back to some sort of mu-metal/stainless outer skin CLD structure yet? 😉
Unfortunately, I am by sheer necessity in those waters now. I was told titanium is about 40% harder than high quality steel, while being only about half the weight. For doctors, the most important benefit is that not one allergy to titanium is known of thus far. For low fi requirements, they use steel 317, the material used for surgical tools. Manufacturers of wristwatches make damn sure you know your timepiece is made from that stee, guaranteed no allergy matters.
But other materials are preferred in other applications, like leg joints which replace hips, for example. I need to operate both my hips this year, as thei degradation is what handicaps me and causes the pain. I learnt that on such cases, ceramics are used, it seems that the Japanese to whom ceramics were originally baisc quality materials, have by now developed them no end. I did ask about titanium myself, but they nixed it straight away. I wondered because of inclusion of perhaps a few servo motors for good measure, powered by belt mounted batteries, Nagra style, but it seems I asked about what is still future technology. Damn it!
Yeah. That is possibly why it was hidden in a place you wouldn't need to go on site. Back then I was more interested in skip diving for aerolam offcuts as that was the hot audio matrial in UK back then (pink triangle, celestion SL600 etc).
dvv, i have a new hip left side since last summer, its a material combo of titanium, ceramics, PE. Works fine and of course, titanium is used because no allergy.
Different makers, different material mix.
Titan is very cool stuff, Airbus A 380 landing gear holding six wheels is made in one piece of it, apx 1500 kg each.
Beryllium is no problem when touch, its poison as a gas and i assume also as a kind of dust, thus a real problem when machining.
Yamaha used that stuff in their TW and MR for the NS 1000 M Monitor when my Memory serves me well. Shure used it for Cantilever Tubes in their top series Cartridges.
For audio i dont see many applications for that exotic and very expensive stuff.
Different makers, different material mix.
Titan is very cool stuff, Airbus A 380 landing gear holding six wheels is made in one piece of it, apx 1500 kg each.
Beryllium is no problem when touch, its poison as a gas and i assume also as a kind of dust, thus a real problem when machining.
Yamaha used that stuff in their TW and MR for the NS 1000 M Monitor when my Memory serves me well. Shure used it for Cantilever Tubes in their top series Cartridges.
For audio i dont see many applications for that exotic and very expensive stuff.
well speaker domes and cantilevers are two good applications where the woo can be laid on thick. Look at the rush to sapphire since the supply of Boron started to dry up by cartridge makers. I still can't work out how the vapour deposition cantilevers were actually made.
I also dont know abouth vapour deposition cantilevers.
I know some makes of QuasiribbonTW MR with vapour deposition, Dali line source for example. They say the carrier material can also be made thinner and thus lesser mass
A japanese maker uses carbon for cantilevers now, the maker of my MC let me choose between alu tube and special treated cactus stinger with carbon inlay for some reasons.
He sez cactus advantage is nearly unbreakable.
But i am happy with my standard alu.
For preamp housing i like when made of a solid alu block, it looks good and surface can be hardened easy. But my pre housing is non magnetic steel plates hold together by alu bars and no visible wiring inside. Sound is ok for me.
I know some makes of QuasiribbonTW MR with vapour deposition, Dali line source for example. They say the carrier material can also be made thinner and thus lesser mass
A japanese maker uses carbon for cantilevers now, the maker of my MC let me choose between alu tube and special treated cactus stinger with carbon inlay for some reasons.
He sez cactus advantage is nearly unbreakable.
But i am happy with my standard alu.
For preamp housing i like when made of a solid alu block, it looks good and surface can be hardened easy. But my pre housing is non magnetic steel plates hold together by alu bars and no visible wiring inside. Sound is ok for me.
ribbons I can understand, but vapour depositing a tube sounds difficult. There is a russian guy on vinylengine who uses cactus a lot for rebuilds. Not for me. Whilst I like exotic bling I do like the cantilever on the Ortofon Rohmann I picked up recently needing a rebuild. Tapered, good diameter, thin wall. Only Aluminium but ticks a lot of boxes. Sadly the rebuild is 5x the purchase cost so will have to wait... (note pic is how it should look, not how mine does look). Oh and machined from solid body for extra audiophile points 🙂.
Attachments
A small clarification of terminology:
Titanium is not a hard material, it rather possesses excellent toughness, i.e. the material property which relates to the amount of energy it can accept before breaking.
Hardness is a surface property, relating to the resistance to scratching (loosely termed), and it is where titanium really does not excel.
Japanese camera manufacturers developed a titanium surface hardening process back in the eighties, which enabled them to produce extra light, and yet durable shutters.
I've got two wristwatches with titanium casings, and the one made of normal titanium shows all usual marks of usage, whereas the one made of hardened titanium looks still as new (both over 15 years old).
Regards,
Braca
Normal treatment for Ti is nitriding. Think SME 3009 SIII. I assume that is what you are referring to?
No idea what process they used at the time. I had a camera with such a shutter, and there was an article about it in a photography magazine.
Titanium surface hardening is apparently still an active research subject.
Ouch. I gather the Rohmann has a very nice stylus as well, some sort of line contact "Ortoline". I have a much more modest MC15 Super MkII which I de-cantilevered during setup before I ever heard it. 🙁 I still have it and keep thinking I should get it retipped somewhere, just to compare to my Denon.
ß metastable titanium two-phase alloy Ti10-2-3.
https://en.wikipedia.org/wiki/Ti-10V-2Fe-3Al
Hi-tech material (under constant monitoring of project PROMITI in this application).
Let’s see if it will better in service the previously used low alloy steel 300M
(stress corrosion issues on the truck -or bogie- beam which you are referring to).
I very much doubt the 1500Kg weight though🙂
For structural materials, hardness is typically measured in HRC (Hardness Rockwell C) or universally referrenced to it.
The HRC hardness is not a surface property, it is a bulk property.
The depth of the indentation - which is actually what the hardness test measures - is an appreciable fraction of a mm.
E.g. that titanium alloy has a hardness range of HRC35 to HRC42. The indentation depth is from 0.13mm to 0.116mm. And this is beneath an initial surface penetration.
Indentation depth (beneath the initial surface penetration)= (100-HRC)/500 (in mm)
George
Attachments
- Status
- Not open for further replies.