Titanium armor

[ChippedHammer]

Has anyone tested the bullet resistive properties of sheet titanium? Titanium is fairly cheap and easy to come by in 6Al-4V form and would be idea for armor plating things (blast shields, trauma plates, cars etc), its light weight and not too hard to machine.

I did find this, its a pretty bad scan but from what I can tell it only relates to the .50bmg

http://handle.dtic.mil/100.2/ADA800063

Anyone have any personal experience? I have some 3mm sheet here but nothing to shoot it with.

Cheers

[iHME]

I don't have personal experience but doesn't some russian flack/bullet resistant vests use titanium instead of kevlar? As far as I know they made some vests with titanium inserts. I will probably buy one some day.

[krysthegreek]

I'm pretty sure that the reasoning behind using Kevlar is that it distributes the impact force of the bullet, dispersing the energy and gradually slowing the projectile down. Titanium, as a hard, brittle metal, is more liable to crack or shatter, producing potential shrapnel that could be worse than just the original bullet.

[neetje]

I thought that inserts were there to protect vital organs (heart, lungs etc.) from blunt force trauma of a bullet impacting on the armor, but they still used kevlar/aramide to stop the bullets themselves.

This is the first document I've seen that is about the armor being something of only titanium. Good find ;)

[Arcticpheonix]

I'm pretty sure that the reasoning behind using Kevlar is that it distributes the impact force of the bullet, dispersing the energy and gradually slowing the projectile down. Titanium, as a hard, brittle metal, is more liable to crack or shatter, producing potential shrapnel that could be worse than just the original bullet.

I believe the other reason behind this, is that unlike Titanium, Kevlar is very flexible and therefore much more comfortable to wear.

In regards to a titanium plate however (instead of the current steel) I think you're right about shrapnel. It would really suck if your "bulletproof" vest was what ended up killing you.

[Demolition Man]

ts light weight and not too hard to machine.

Debatable, from my personal experience it is brittle and warps and blues fairly easily under machines, but thicker items can be metal braked easily, and you can english wheel it for curves...solid machining though? hard and can easily damage the metal.

Of course, you could always try a couple of plates out, not just different thicknesses, but different alloys too. And since they would be inserts, around 4x5 sizes or so, http://www.smallparts.com/ this site should help you out with that. I use them for tubing, but they sell sheet and plate metals there too.

[Jacks Complete]

Damn, lost that post...

To recap, titanium is used in the CRISAT soviet body armour. From the top of my head, it is 2mm Ti plate, and 20 layers of Kevlar weave. The standard 9mm fails to penetrate at 10ft. The new range of high penetration, low impulse cartridges rip clean through it at 200m.

Armour theory says you want a very hard surface to "break" or otherwise disrupt the projectile. With steel armour, you are best to have a very hard face, then a ductile, shatter-resistant back. With a composite armour, your backer is generally Kevlar, Goldflex or Nomex or some other aramid fibre.
Of course, you are generally trying to stop a hardened steel projectile at small-arms levels. Hence, using steel will often give little advantage, plus it is heavy. This is why we see ceramics used for the plates, and, sometimes (in, for example, the RAFOSS) ceramic penetrators. (An additional advantage is that ceramics are brittle. When they shatter, they take energy from the projectile as well as disrupt it)

Titanium has advantages over steel in two regards for this application. One, it is half the weight of steel for the same strength. This means that, roughly, you should need 1Kg of Ti where you would need 2Kg of steel. However, as it is 1/4 the mass, your 1mm steel plate needs to be a 2mm thick Ti plate.
Secondly, TiN is very much harder than steel, and even plain Ti can be made as hard, if not slightly harder, than steel. With a coating of Titanium Nitride, your plate will be significantly harder than any steel and slightly harder than most ceramic penetrators. (Of course, you can also TiN coat steel!)

If your plate punches through, the bits will be stopped by the Kevlar behind. However, I don't know the results of any research into whether the expansion of the hole as it peels open has a negative effect on the aramid behind. Personally, I would suspect that two thinner plates of ultra-hardened steel or titanium over Kevlar would have a significantly greater effect than a single, double thickness plate.

Anyone else have any experience with this stuff?

[sfc1620]

Titanium + Ceramics for the win.

http://www.youtube.com/watch?v=KS0pSwdQfbY

[Jome skanish]

Perhaps combining it with liquid armor would prove its worth as a backing material. SiC particles in polyisobutylene goop, saturated just to the point where it is rheopectic [hardens if mechanically stressed]

A bit OT, but I wonder how strong would homemade SiC/polymer plates would be. SiC is found in various grades as a grinding material used to polish stones in those ball-mill things.

[iHME]

How fast is the rheopectic effect with SiC?
But if it is backed by some Ti plate it could be a sweet thing to own.
As a curiosity atleast.

[Jacks Complete]

Just to add something I found the other day.

The Indian (or Pakistani, 100% unsure which) army has cheap sets of body armour. These are not titanium, but steel. They are simply steel RHA plates about a foot square, front and back, with two holes in each and two shoulder straps! They stop a 7.62 and a 5.56 without any issue.

Obviously inflexible, very heavy, but will save your life from almost any impact, blade or gunshot. And seriously cheap!

[iHME]

I'd suspect India, they have so much people and men that getting kevlar & ceramic body armor for them would brake the bank. But making a simple steel plate body armor would be fun, sure it would not stop proper AP ammo but soft bullets would probably be stopped.
Remember that police and other similar entities use JHP and hollow points to have the least penetration possible to avoid shooting through multiple buildings.

Building a steel one would be cheap to say at least. And who would not want to own one?

Also what about a "laminated" armor from sheet steel and titanium?

[Jome skanish]

That'd make it both heavy AND expensive.

Then again, the price issue with titanium is mostly related to the difficulty in machining the stuff. 6.5$/kg ain't that much by itself compared to most military gear.