# Titanium **URL:** \ **Category:** Factual Questions\ **Created:** [September 24, 2001, 1:09pm UTC](https://boards.straightdope.com/t/titanium/83476 "2001-09-24T13:09:20Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![AndyJ](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@AndyJ](https://boards.straightdope.com/u/AndyJ)\ **Post date:** [September 24, 2001, 1:09pm UTC](https://boards.straightdope.com/t/titanium/83476/1 "2001-09-24T13:09:20Z")
How thick would a piece of titanium have to be to stop a round fired from a rifle at about 100m, say a 5.56 round? ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [September 24, 2001, 1:15pm UTC](https://boards.straightdope.com/t/titanium/83476/2 "2001-09-24T13:15:21Z")
Do you mean pure, elemental titanium, or titanium steel? ---
**Author:** ![AndyJ](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@AndyJ](https://boards.straightdope.com/u/AndyJ)\ **Post date:** [September 24, 2001, 1:16pm UTC](https://boards.straightdope.com/t/titanium/83476/3 "2001-09-24T13:16:27Z")
Which ever is strongest. But has to be light aswell. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [September 24, 2001, 1:32pm UTC](https://boards.straightdope.com/t/titanium/83476/4 "2001-09-24T13:32:01Z")
Body armor. > **[America's #1 Custom Holsters, Communication Devices, Body Armor, and M](https://safariland.com/)** > > Security products including duty gear, holsters, body armor and tactical headsets for Law Enforcement, Military and First Responders. > [@](#): > > T-15 Titanium II+ Metal plate That’s a “trauma plate”. [http://www.code4pro.com/searchresults.asp?reference=advanced&varCategory=2](http://www.code4pro.com/searchresults.asp?reference=advanced&varCategory=2) > [@](#): > > Second Chance TITANIUM T-15 ARMOR PLATE 7 > 7"X10" Weighs 8oz and is 1" thick [http://www.code4pro.com/productdetails.asp?SKU=SC13-L](http://www.code4pro.com/productdetails.asp?SKU=SC13%2DL) > [@](#): > > Titanium plate is wrapped in aramid spall cover. It offers protection to level IIIA when worn with and in front of your vest. Provides the ultimate balance in protection, weight and concealability. Will stop all KTW, 9mm ,.44cal and 30cal carbines. So, 1" will stop the aforementioned bullets. I’ll let the ballistics geeks take it from here. 😃 ---
**Author:** ![AndyJ](https://avatars.discourse-cdn.com/v4/letter/a/8491ac/32.png) [@AndyJ](https://boards.straightdope.com/u/AndyJ)\ **Post date:** [September 24, 2001, 1:46pm UTC](https://boards.straightdope.com/t/titanium/83476/5 "2001-09-24T13:46:22Z")
For the quick reply Duck Duck Goose. I’ve seen the vests the police over here, the UK, use. But they tend to have, I think, ceramic inserts. I think they’re more designed to stop knife attacks rather than bullets. ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [September 24, 2001, 2:09pm UTC](https://boards.straightdope.com/t/titanium/83476/6 "2001-09-24T14:09:15Z")
On my quickie tour of body armor websites, I saw that the laminated Kevlar/fiber/resin, etc. vests are considered better for the guy wearing them, as metal trauma plates tend to deform inwards when the bullet hits, leading to severe bruising at the very least. Depends on the thickness of the plate and the caliber of the bullet, etc. ---
**Author:** ![geepee](https://avatars.discourse-cdn.com/v4/letter/g/ebca7d/32.png) [@geepee](https://boards.straightdope.com/u/geepee)\ **Post date:** [September 24, 2001, 3:57pm UTC](https://boards.straightdope.com/t/titanium/83476/7 "2001-09-24T15:57:05Z")
hmm well the police here used to have these vests with steel plates in them for protection against knives in a hostage situations and stuff , then this woman while negotiating thought it was too heavy took it off and subsequently was stabbed to death which made police demand lighter ceramic and kevlar with steel insert vests for bullet and knife protection , however when police in the UK are confronted by people with knives , or any other dangerous weapon like a gun they are trained to shoot in the upper chest area until you fall ---
**Author:** ![DougC](https://avatars.discourse-cdn.com/v4/letter/d/7feea3/32.png) [@DougC](https://boards.straightdope.com/u/DougC)\ **Post date:** [September 24, 2001, 4:37pm UTC](https://boards.straightdope.com/t/titanium/83476/8 "2001-09-24T16:37:14Z")
- - - I dunno the answer to the question, but I point out that most “common” Titanium alloys are somewhat lighter than steel but somewhat stronger than aluminum. There is steel available that is stronger than Titanium and Aluminum available that is lighter. (I am speaking of commonly-available metal stock- -exotic space shuttle/fighter-jet stuff might be better) - The main advantage of Titanium is that some alloys of it have large fatigue life (the ability to withstand repeated bending without cracking). Parts made from it must be carefully engineered to exploit this characteristic, though. One main use, for instance, is for hydraulic lines on large aircraft. - Titanium is available from suppliers online (Shapiro Supply, in my neighborhood), but not many really stock much of it because it’s difficult for builders to work with: it’s expensive (because it has to be _electrically_ melted out of white beach sand), it is difficult to cut or drill mechanically and it requires special welding techniques with expensive equipment to join it well. It usually costs about nine times as much as 4130 steel. - MC ---
**Author:** ![Qis](https://avatars.discourse-cdn.com/v4/letter/q/b9bd4f/32.png) [@Qis](https://boards.straightdope.com/u/Qis)\ **Post date:** [September 24, 2001, 4:37pm UTC](https://boards.straightdope.com/t/titanium/83476/9 "2001-09-24T16:37:18Z")
\however when police in the UK are confronted by people with knives , or any other dangerous weapon like a gun they are trained to shoot in the upper chest area until you fall\ Erm. UK- as in United Kingdom? I want aware the police here carried firearms on routine patrol. and i wouldnt think a thug witha knife would wait around for the armed response team to show up. Guy with a gun… possibly. knife - nae chance. Cant even rember what my point was now. Oh well. I love you all. ---
**Author:** ![Andy](https://avatars.discourse-cdn.com/v4/letter/a/aeb1de/32.png) [@Andy](https://boards.straightdope.com/u/Andy)\ **Post date:** [September 24, 2001, 5:06pm UTC](https://boards.straightdope.com/t/titanium/83476/10 "2001-09-24T17:06:18Z")
> [@](#): > > \*Originally posted by MC \* > Titanium… …it’s expensive (because it has to be _electrically_ melted out of white beach sand)… That sounds like alchemy to me…😉 Beach sand is silicon dioxide. ---
**Author:** ![Andy](https://avatars.discourse-cdn.com/v4/letter/a/aeb1de/32.png) [@Andy](https://boards.straightdope.com/u/Andy)\ **Post date:** [September 24, 2001, 5:11pm UTC](https://boards.straightdope.com/t/titanium/83476/11 "2001-09-24T17:11:45Z")
Hmm…they do seem to call it beach sand (rutile)…I’m confused (it’s not hard)… ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [September 24, 2001, 5:19pm UTC](https://boards.straightdope.com/t/titanium/83476/12 "2001-09-24T17:19:56Z")
Rutile? Wasn’t Eric Idle a Rutile? Now _I’m_ confused… 🙂 ---
**Author:** ![Padeye](https://avatars.discourse-cdn.com/v4/letter/p/a9a28c/32.png) [@Padeye](https://boards.straightdope.com/u/Padeye)\ **Post date:** [September 24, 2001, 6:05pm UTC](https://boards.straightdope.com/t/titanium/83476/13 "2001-09-24T18:05:22Z")
To add to the confusion there is more than one kind of 5.56mm ammunition. The classic M855 is an ordinary FMJ boat tail bullet with lead core and gilding metal jacket weighing approx 55 grains. The new SS109 has a 62 grain bullet with a small steel tip in the core that helps armor penetration. FWIW the ATF excluded this ammunition from its definition of “armor piercing” ---
**Author:** ![Tranquilis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tranquilis/32/3639_2.png) [@Tranquilis](https://boards.straightdope.com/u/Tranquilis)\ **Post date:** [September 24, 2001, 7:23pm UTC](https://boards.straightdope.com/t/titanium/83476/14 "2001-09-24T19:23:16Z")
To clear-up the **Ti** ore questions, go [here](http://helios.physics.uoguelph.ca/summer/scor/articles/scor25.htm). > [@](#): > > Although long known and abundant, titanium remained almost a laboratory curiosity until about thirty-five years ago. The reason for this neglect is the difficulty of extracting the elemental metal from the compounds in which it naturally occurs. Even today it is produced only in a batch process, and no continuous process exists as for other structural metals. In spite of this difficulty, world production is 100,000 tonnes annually, with just under half of that being produced in the U.S.S.R. and the rest in the U.S.A., Japan and the U.K. > The useful ores include titanium dioxide, a mineral called rutile which occur as beach sands in Australia, India and Mexico. Most mined titanium ore is not used to make the metal. Titanium dioxide is a very versatile white pigment used in paint, paper, and plastic, and consumes most of world production. Another important ore is ferrous titanate, or ilmenite, which is found in the Ilmen mountains of Russia. ---
**Author:** ![Tranquilis](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tranquilis/32/3639_2.png) [@Tranquilis](https://boards.straightdope.com/u/Tranquilis)\ **Post date:** [September 24, 2001, 7:33pm UTC](https://boards.straightdope.com/t/titanium/83476/15 "2001-09-24T19:33:14Z")
> [@](#): > > **To add to the confusion there is more than one kind of 5.56mm ammunition…** I think for our puposes here, we can just look at what is necessary to meet Threat-Level III (.308 Win) standards. ---
**Author:** ![Kamandi](https://avatars.discourse-cdn.com/v4/letter/k/5daacb/32.png) [@Kamandi](https://boards.straightdope.com/u/Kamandi)\ **Post date:** [September 24, 2001, 9:55pm UTC](https://boards.straightdope.com/t/titanium/83476/16 "2001-09-24T21:55:42Z")
> [@](#): > > \*Originally posted by Duck Duck Goose \* > Second Chance TITANIUM T-15 ARMOR PLATE 7 > 7"X10" Weighs 8oz and is 1" thick > > So, 1" will stop the aforementioned bullets. I’ll let the ballistics geeks take it from here. 😃 \*\* I’d just like to point out that titanium has a density of approximately 0.16 pounds per cubic inch. A 7in X 10in X 1in thick plate would weigh more than 11 pounds, not 8 oz as quoted above. The 1in thickness must be made up of a composite of titanium plus other materials. Other approximate densities (exact density depends on alloy): Aluminum: 0.10 lb per cubic inch Steel: 0.28 lb per cubic inch Lead: 0.40 lb per cubic inch Depleted uranium: 0.66 lb per cubic inch Kevlar fiber: 0.05 lb per cubic inch (roughly)