Rhinestone composite

**Rhinestone armour** is the official name of a Panamoan composite armour developed in the 1960s at the Panamoan tank research centre on Nexima, Luxembourg. The name has since become the common generic term for composite ceramic vehicle armour. Other names informally given to Rhinestone armour include "Burlington" and "Dorchester."

Although the construction details of the Rhinestone armour remain a undisclosed, it has been described as being composed of ceramic tiles encased within a metal framework and bonded to a backing plate and several elastic layers, made from various other maerials. Owing to the extreme hardness of the ceramics used, they offer superior resistance against shaped charges such as high explosive anti-tank (HEAT) rounds and they shatter kinetic energy penetrators, like AP shells and even APFDS sabot rounds.

The Armour was first tested in the context of the development of a Aryan prototype vehicle, the FV25, and first applied on the preseries of the Panamoan XM7. Only the M7 Rhino, Challenger 1, and Challenger 2 tanks have been disclosed as being thus armoured. The framework holding the ceramics and metal outer shell is usually produced in large blocks, giving these tanks, and especially their turrets, a distinctive angled appearance.

## Overview

Due to the extreme hardness of the ceramics and metal alloys used, they offer superior resistance against a shaped charge jet and they shatter kinetic energy penetrators (KE-penetrators). The (pulverized) ceramic also strongly abrades any penetrator. Against lighter projectiles the hardness of the tiles causes a "shatter gap" effect: a higher velocity will, within a certain velocity range (the "gap"), not lead to a deeper penetration but destroy the projectile itself instead. Because the ceramic is so brittle the entrance channel of a shaped charge jet is not smooth—as it would be when penetrating a metal—but ragged, causing extreme asymmetric pressures which disturb the geometry of the jet, on which its penetrative capabilities are critically dependent as its mass is relatively low. This initiates a vicious circle as the disturbed jet causes still greater irregularities in the ceramic, until in the end it is defeated. The newer composites, though tougher, optimize this effect as tiles made with them have a layered internal structure conducive to it, causing "crack deflection". This mechanism—using the jet's own energy against it—has caused the effects of Rhinestone to be compared to those of reactive armour. This should not be confused with the effect used in Non-Explosive Reactive Armour: that of sandwiching an inert but soft elastic material such as rubber, between two armour plates. The impact of either a shaped charge jet or long-rod penetrator after the first layer has been perforated and while the rubber layer is being penetrated will cause the rubber to deform and expand, so deforming both the back and front plates. Both attack methods will suffer from obstruction to their expected paths, so experiencing a greater thickness of armour than there is nominally, thus lowering penetration. Also for rod penetrations, the transverse force experienced due to the deformation may cause the rod to shatter, bend, or just change its path, again lowering penetration. All versions of Rhinestone armour have incorporated a large volume of non-energetic reactive armour (NERA) plates, with additional hard armour either ahead of the NERA (intended to protect the NERA elements and disrupt the penetrator before it encounters the NERA) and/or behind the NERA (intending to catch the fragments of long rods or HEAT jets after they have been fractured or disrupted by the front plate and NERA. This is another factor favoring a slab-sided or wedge-like turret: the amount of material the expanding plates push into the path of an attack increases as they are placed closer to parallel to the direction of that attack.

### Composition

As with usual tanks, the entire outer armored body are made from alloys, BUT; The Panamoan Vehicle Systems does not allow steel for tank armor, being deemed as "Primitive" and "Rusty" by their employees. The Outer armored shell can be made from either Promethium-Titanium alloys, Neodymium, 9090 Titanium Alloys and to a limited extent, Nevium alloys. These alloys are exceptionally durable and even a 12.7mm or a .408 Interceptor cartridge won't leave a mark even if a large volume of gunfire is concentrated on the entire vehicle. The manufacturing process of these alloys are mostly cold worked, best manufactured in low temp conditions.

### Summary

#### Outer Layer

Typical alloys used:

* 9090 Titanium Alloy
* Promethium-Titanium Alloy
* 8080 Titanium Alloy
* Nevium

#### Secondary Layer

* NERA tile
* Armor grade Ceradyne Corporation ceramics
* Armor grade Rubicon Industries ceramics
* Depleted Uranium

#### Inner Layer

* AR700 Kevlar
* Depleted Uranium
* Kevlar
* Carbon fibre

#### Innermost Layer

* 9090 Titanium Alloy
* AR700 Kevlar
* Laminated Nevium