Main Battle Tanks and Armour Technology

[Damian]

Also, there are munitions, where, you actually have a jet of super-heated molten copper than can drive a hole through several inches of steel.

This is so called Shaped Charge Warhead that creates Shaped Charge Jet, this type of warheads are used in RPG's, ATGM's and HEAT ammunition.

The real guts behind the AP properties javelin rocket, apart from the top-down and fire and forget is its ability to get past reactive armour... and the huge limitations of explosive reactive armour are greatly exposed by these two charged explosives.

Electric/ultrasonic reactive armour is probably the way to go in the future.

ERA is not obsolete yet, there are types of ERA that can protect against tandem warheads of some of RPG's and ATGM's. This type of ERA is also multilayer thus more bulky than typical one layer ERA. For example Ukrainian Douplet modules use Knife ERA packed in 2 or 3 layer package. US Army's use on it's M1 tanks TUSK kit, layered M19 ARAT ERA, same ERA is used on M2 IFV's and was also adopted for Stryker APC.

Russian 4S23 Relikt ERA is claimed to be effective against tandem warheads.

Electric/ultrasonic reactive armour is probably the way to go in the future.

Not nececary, we do not know if such armor is effective against APFSDS ammunitions, if it is not as universal as in case of heavy ERA, than it might be just another of experimental armor designs.

 

[methos]

Nothing is molten in shaped charges.

 

[pmaitra]

Nothing is molten in shaped charges.

You are probably not aware (see the entire video):

 

[Damian]

Yeah that's true, however as false it is, it is a very popular opinion that this is molten metal.

High explosive anti-tank warhead - Wikipedia, the free encyclopedia

Contrary to a widespread misconception perpetuated by the acronym, HEAT rounds do not depend in any way on thermal phenomena for their effectiveness. In particular, the shaped charge jets do not "melt their way" through armor, only reaching 500-600°C, and instead rely on extreme pressure to force a hole through the armor.

You are probably not aware (see the entire video):

This is a typical TV show, in reality shaped charge jet is not a molten metal.

 

[Damian]

Shaped Charge Jet is not a molten metal per se. It do not penetrate armor by using high temperatures but extreme pressures, these extreme pressures and speed with jet travels, makes it's interaction with armor like there would be liquids instead of metal. But this not have anything with molten metal. There is just not enough temperature to make metal to be molted.

 

[Bhadra]

Shaped Charge Jet is not a molten metal per se. It do not penetrate armor by using high temperatures but extreme pressures, these extreme pressures and speed with jet travels, makes it's interaction with armor like there would be liquids instead of metal. But this not have anything with molten metal. There is just not enough temperature to make metal to be molted.

It creates a slug effect... molten mass rushing through the point of concentration of converging waves .... of course you might have seen copper slugs..

 

[Damian]

It creates a slug effect... molten mass rushing through the point of concentration of converging waves .... of course you might have seen copper slugs..

AFAIK in not even a single publication about anti tank ammunition, shaped charge jet is not called a molten metal, neither any of specialists want to call it and they say it is something different than just a simple molten metal.

There were plenty of such discussion on TankNet forums, and the guys who have incredible knowledge about tanks, were also saying that it is not a molten metal as it is popularly claimed.

http://www.globalsecurity.org/military/systems/munitions/bullets2-shaped-charge.htm

That might help, nowhere here it is mentioned that jet is a molten metal. It is rather a deformed metal, mainly because shaped charge jet linear is made from very thin metal, easy to be deformed by explosion, thus creating a jet.

 

[pmaitra]

Anyway, there some interesting concepts, and many modern munitions are implementations or improvised implementations thereof:

• Misznay–Schardin Effect
• Monroe Effect

 

[methos]

I think it is a missinterpretation. The jet is not molten and it also does not melt the armour. Still the contact area between shaped charge jet and (metal) armour behaves pretty much hydrodynamic.

 

[Bhadra]

Nothing is molten in shaped charges.

Why charges are shaped and what shapes those?
Charges are shaped to produce a pattern of shock waves so that a jet (concentration) at a particular place forms.

This is achieved by shaping the explosive in a particular angle and providing it a metallic case of the same shape to withhold certain amount of pressures of shock waves and allow shock waves to concentrate and build higher pressure.
At very high pressure, the temperature achieved is very high.
Shock waves penetrate the target and high temperatures produces a molten mass of the nose cone (generally copper or aluminium).
That molten mass follows the jet of high explosive waves penetrating the target and forming a molten slug .

 

[Damian]

Mind I remind You that temperature of shaped charge jet is relatively small, so nothing is melted there. Shaped charge jet is formed by deforming cone shaped insert.

 

[Bhadra]

AFAIK in not even a single publication about anti tank ammunition, shaped charge jet is not called a molten metal, neither any of specialists want to call it and they say it is something different than just a simple molten metal.

There were plenty of such discussion on TankNet forums, and the guys who have incredible knowledge about tanks, were also saying that it is not a molten metal as it is popularly claimed.

Shaped Charge

That might help, nowhere here it is mentioned that jet is a molten metal. It is rather a deformed metal, mainly because shaped charge jet linear is made from very thin metal, easy to be deformed by explosion, thus creating a jet.

you are right technically.
The aim of shape charge is not to damage through molten mass but through concentration of shock waves producing a temperatures beyond the resistance of armour so that there is a big hole at the point of concentration of shock waves. The result of a whole being produced is not drilling but concentration of very high temperature shock waves at a point.

Molten mass of nose cone also taking part into this process is an extra side effect. However, every anti tank HEAT weapon will produce a molten mass due to nose cone being there or the charge will not be shaped.

 

[Bhadra]

Mind I remind You that temperature of shaped charge jet is relatively small, so nothing is melted there. .

Pray tell me that there is neither temperature not a shot, then what makes the hole into armour? Unless you mean HEAT are meant to scare the tank crew.

 

[methos]

The hole in the armour is made by a very long and very thin metal "sting" moving at very high speeds.

 

[Damian]

you are right technically.
The aim of shape charge is not to damage through molten mass but through concentration of shock waves producing a temperatures beyond the resistance of armour so that there is a bog hole at the point of concentration of shock waves. The result of a whole being produced is not drilling but concentration of very high temperature shock waves at a point.

Molten mass of nose cone also taking part into this process is an extra side effect. However, every anti tank HEAT weapon will produce a molten mass due to nose cone being there or the charge will not be shaped.

What shockwaves? Armor is perforated by using extreme pressure not some shockwaves.

And no, there is no melting of both armor and jet, jet is just deformed metal insert (cone shaped) that is moving extremely fast and when it hits armor it penetrates it by means of that extreme pressure. Technically it is similiar to APFSDS penetrator penetration mechanism.

However contrary to APFSDS penetrator, shaped charge jet allmost do not have density (nad mass), thus it is easier to protect vehicle against it by using special armors.

But both in case of APFSDS penetrator or shaped charge jet, there is no such phenomenon like melting metal during penetration.

Simply because there is not enough high temperature to do so, 500-600C is what, nothing, Gas Turbine engine is working in a temperature of 815C and is not melting, nor it's internal elements, nor external, and many of them are not even some special metal more resiliant against high temperatures.

Pray tell me that there is neither temperature not a shot, then what makes the hole into armour? Unless you mean HEAT are meant to scare the tank crew.

As Methos said, and as I said, it is an effect of high pressure. explosive charge detonation deforms metal insert in warhead thus creating a jet that is extremely narrow (it is avarage 4mm in diameter) and long, and the same explosion accelerates this jet to extreme speed, thus when jet strikes armor, pressure is so high that this jet is capable to penetrate armor.

Remember that shaped charge jet phenomen is something very... unique and it is not fully understanded by our physics, thus explaining it is very difficult.

 

[methos]

Shaped charge during flight and penetration.

 

[Damian]

Wow, incredible photos! Thanks Methos.

 

[Bhadra]

What shockwaves? Armor is perforated by using extreme pressure not some shockwaves.

.

neither temperature nor shock waves?.
And what creates pressure? some invisible force ??

some kinetics? what are you saying..

 

[Damian]

Eh.... shaped charge jet is accelarated by explosion of explosive filler in the warhead. When explosive filler detonates it:

1) deforms cone shaped metal insert creating shaped charge jet.
2) accelerate this jet to extremely high speed.
3) This jet traveling at extremely hight speed hitting armor have enough kinetic energy and there is enough pressure to penetrate armor.

It is simplified and I do not know how I can explain this simpler (especially with my english limitation).

I think that with shockwave You confused HEAT ammunition with HESH/HEP ammunition that indeed use a shockwave.

 

[Godless-Kafir]

I wonder if shaped charge can be made at home? Does it require C-4 or does cracker powder(silver nitrate) good enough!