Wouldn’t it catch fire ?

 

His last words were, "This body armor is a crock!"

 

From the research I found, it said the flash point exceeds 160°f.

 

That's very low. I don't know if hot lead could set it off, but something as small as a spark will, especially if it fragments.

Think about how easy it is to start a fire with a magnesium fire starter.

I would not consider magnesium to be a good choice for body armor.

 

Magnesium catches fire well when in a fine form like powder or shavings.

Magnesium in a normal state isn't very malleable. Magnesium rims, like aluminum rims, on cars that have been in accidents or have had the lugs way over torqued just break and crack.

My guess would be that magnesium body armor would just shatter and turn into a bunch of secondary projectiles.

 

That's why I specifically stated, "alloy" in the thread title.

Magnesium fire starters are a softer, non-alloy metal with intended sparking abilities.

Most people aren't standing directly next to someone with a shotgun, for example, which potentially could provide direct flame. Regardless, magnesium fire starters typically spark but don't start a fire until after multiple strikes by the steel.

Ammo is also not typically made from steel; it is copper jacketed lead core, or lead slugs or pellets for SG's. Lead does not spark magnesium fire sticks.

My original thoughtd were, perhaps a magnesium / tungsten carbide or titanium. Even aluminum may be worth looking at as a potential alloy.

Here is an old link from 2014 describing the strongest mag alloy to date at that time, which has an even higher FP than pure magnesium alone, making it a potentially useful element for body armor:

Development of the world's strongest magnesium alloy

There is strong demand for the improvement of the mechanical properties (particularly the strength) of magnesium (Mg) alloys to meet the growing industrial applications of structural materials.

phys.org

Here is a basic list of different metal ores as a reference:

List of Metals

Most elements can be considered metals. This is a list of metals in order of increasing atomic number and a summary of their properties.

sciencenotes.org

...and one specifically on mag's properties;

Magnesium Facts - Mg or Atomic Number 12

Discover key facts about magnesium, including its properties, uses, abundance, health benefits, and potential toxicity.

sciencenotes.org

According to the last link above, magnesium's melting point is:

Melting Point: 923 K (650 °C, 1202 °F)

Which is considerably higher than the original info I found previously.

Here is more info directly on mag alloys:

https://en.m.wikipedia.org/wiki/Magnesium_alloy

That link contains info describing its use in coating nuclear rods, which get extremely hot, even submersed in heavy water.

My point is, it is unlikely to spontaneous combust on its own; steel is rarely used for munitions in bullets, hence the reduced likelihood of sparking; and an alloy not only gives magnesium higher tensile strength, but certainly additional resistence to flame and burning. That its melting point is 1202° f is also a bonus.

Anyway, steering the conversation back on track, do we have anyone with a metalurgy background, or knowledge of metal alloys? With scientists actively studying this area for high tensile strength, lightweight materials and ability to shape the alloy into a custom form, perhaps this would be an area of further research worth pursuing.

 

You should look into fiberglass if looking for a capable and lightweight material for body armor. Not sure about Magnesium but fiberglass would be cheaper and a lot easier to work with, needless to say available just about anywhere.

 

That is something I hadn't yet considered, but boy does that have possibilities. I sure wish I had the funds, workshop, knowledge and abilities to work on these ideas.

Thanks, Merlin. That's a heckuva idea worth exploring.

 

MOA,

I've used body armor in the military and civilian job to comply w/ insurance requirement. Am retired now.

The main reason body armor not rated for rifles due to wearer's loss of mobility.

If seeking protection from the real personal weapons like your mention of 762 x 51, place emphasis on the helmet.

 

Dont know a whole lot about metallurgy but here is something I do know:

Magnesium and Aluminum were used by Volkswagon in their aircooled engine for many years.
The ratio of Mg to Al was adjusted a few times over the years but one thing that remains constant was that it was a soft metal. Soft as in you can cut a sliver off with a pocket knife.
It also does not have a high tensile strength, it is very easy to break off chunks. Odd how it can be soft and brittle at the same time.
I know from experience that a 5.56 will punch right through said engine block.
Lastly, when used in a bonfire, they burn hot as hell.

While this does not directly answer your question, you can narrow down the various combinations by skipping the Mg with Al and move on to the next one.

 

Cannon,

Was hesitant to scribble this but basically common info, .....

We teach in COIN that some powdered mag sprinkled onto something does wonders for field improvisions.

I know a good metal to research: spent uranium.

 

I've seen .308 ball punch through inch thick aluminum and magnesium pieces without problem. It better to stick to known armour technology .

 

Magnesium would suck as armor. Anyone that ever saw a mag wheel get destroyed knows that, they handle stress, but not impact.
An alloy that made it function as armor would wipe out any of the things being considered as beneficial, like weight.
There’s a reason the people that make armor aren’t using it.

 

There’s a reason the people that make armor aren’t using it.

Yep. If it would work, the military would be using it.
There's no shortage of manufacturers who would love to take trucks full of taxpayer money
if they could sell "better" armor.

IOW, I'm pretty sure someone has thought of that idea already. People been making armor for over 3,500 years.

 

The same question could also apply to titanium (although much harder to mold). I do know that magnesium can be highly volatile once ignited, but if it were part of an alloy ... maybe that problem could be mitigated. I'd also be interested in its stopping power.

Interesting concept.

 

They use titanium as armour on some helicopters to protect the pilots. It's pretty thick. When we were armouring our Airbus 310's to fly into Afghanistan we used 1/2 inch panels of some bullet proof material . Some of the guys that were shooters borrowed some off cuts to test at the range. It stopped .308 and 30.06 . I have a 6 inch square chunk I kept as a souvenir . Unshot.

 

A couple years ago I bought 2 plates from a Texas company that are titanium, much lighter than steel. From what I understand though, the price of titanium has skyrocketed so I'm not sure if they're still available. I run the Ti plate in front and a poly plate in the rear, I don't plan on getting fire from the rear. I also have a steel groin plate. It's still a heavy rig but more manageable than all steel but I don't plan on humping mountains in it.

 

Ti plate is still available, here's what I have.

Titanium Armor Plate - Mantis™ "The apotheosis of body armor systems"

The Mantis Titanium Armor Plate, is body armor for those who will accept no compromises. At just 5.45 pounds for full RF2 protection.

www.adeptarmor.com

 

Love it!
And although it may be a bit pricier than it was, say, 2 years ago, at $489 fot a Ti front plate really isn't that bad at all. It's at least do-able, even if it wipes out most of a paycheck.

Thanks for the link!

 

Aluminum I think would be better.

 

Sparks aren't the only thing that causes heat at the impact point. Kinetic Energy causes quite a bit when the bullet impacts the surface. On materials where thew bullet punches right thru, the heat generated would be minimal. However, on materials that actually stop the bullet, I'm betting that the K/E temperature is fairly high.

Some time back, I was looking into plastic materials for body armor. (As in cheap substitutes!) "Slippery UHMW Polyethylene"was looking good but I never got past the basic research stage. It's light enough so a two inch thick sheet of it tapered down at the armpits is a maybe? My thoughts on it were to layer thinner layers of it with something like thin Kevlar. (Thin Kevlar is cheap, relatively speaking)

Do NOT use Fiberglass! They issued layered Fiberglass cloth body armor vests to the troops in the middle times of Vietnam. They would stop a ricochet...most of the time. They never stopped a 7.62 Russian round coming on full power. What they were good for, was to blow Fiberglass splinters into the bullet hole.

In some cases when the bullet was near the end of it's lifespan, it wouldn't have enough power to just pop a hole and keep on going trailed by Fiberglass splinters. It would have to stretch the fabric out and finally break a hole or not. It didn't really matter whether the bullet actually penetrated or not. The wound looked like a giant funnel all of the way thru the body. The vests started getting lost in battle, fell out of helicopters, misplaced, just plain refused to be worn, etc. etc.

 

Titanium might be more practical.

 

 

The problem is not how "hard" the metal is. It is in, what is the crystalline structure of your metal. An alloy of 3 parts titanium and one part gold would be more ideal than magnesium, if weight is your concern. If weight is not an issue the manganese would be more suitable. Since we are talking body armor and not vehicular armor, then I will assume that the titanium/gold alloy would be your best bet. But as with anything else, the better the quality of desirable outcome, the costlier it would be. Gold can be found almost everywhere there are scrap electronics, so that would not make it cost prohibitive but titanium on the other hand is only found naturally in two places. I forget the first but the second is Russia. So it is naturally going to cost more. There is an alternative though, and that is there are sites on the net that show you how to manufacture titanium at home. I do not know the quality of it and will not even try to guess, but know the info is out there. Research metallurgy and learn about how the crystalline structure of each metal determines how it is interlaced. Is crosshatch or linear, etc.

 

As a volunteer fireman I once watched a Volkswagen Van with a as I told had a Magnesium Engine Block burn to the ground… Water was no good and it burned so hot and bright you could not look at for very long at one time…Burnt a huge hole in the parking lot assault…
Pretty Cool to see…

 

Yep. VW air cooled motors were magnesium, not aluminum. They will flash burn your eyes if you look at it while burning.

 

for anyone interested, old 1970's samsonite luggage used magnesium for the metal case strap and hinges. The old grey and the burgundy suitcases at yard sales are an inexpensive source if you need magnesium for a project.

That's all i've got to say about that.

 

Just buy a proper rated vest. Bad idea making it when you can just buy it. It's tested it has coatings. Ceramic plates are lighter but don't like to be dropped. They can Crack. Steel works best and is the most durable but is heavy. You can go with a liquid body amount that's experimental but it doesn't work in all weather conditions and doesn't work well.

 

I completely disagree on what's best, ceramic/poly is the best IMO. My ceramic hybrid are multi hit capable, less than half the weight, and protect at a higher level than steel. They are thicker, but it is so much better in the other areas that the thickness doesn't matter as much. I have 3 sets of plates and several sets of kevlar. Steel is good if that's all you can get, but it is much harder to move swiftly in, it's amazing what an extra 8-10 un-natural pounds will do to your movement.

They work better in static environments.

 

I wonder what temp tracer rounds burn at......hmm, lol.

 

ummm...M855 just sayin

 

I love the steel is thinner argument. Guys justify buying it on that premise then double stack mags and all kinds of crap on their plate carrier. While I agree being as close to the ground as you can get is a good idea, being fast is better and lighter = faster. Besides your talking what 3/8 or 1/2 in difference between ceramic and steel?? Wanna stop AP rifle rounds?? Not with a level 3 steel plate you wont..

 

A long time ago I read that experiments with body armour were being done with....cornstarch. Funny stuff, when mixed with water it almost solidifies when touched, instantly. Have not read anything more about it.

Just musing, saw an experiment with papercrete as a wall reinforcement. Homemade tests showed some good resistance to several different caliber rounds.