More on armour...

Armourplas.

Armourplas is a dense synthetic plastic that has been used in the production of armour since before the Dark Age of Technology. It is used in everything from Imperial Guard uniforms to Titans to Fortifications.

Armourplas is a dense (relative density ~2) rubber-like material with a natural grey or tan colour (depending on its manufacturer), though it is easily dyed any colour required. Thin ‘plates’ of armourplas is sewn into many military/para-military uniforms to give protection against a variety of attacks, from kinetic attacks to las-blasts. It has been shown that a 1cm thick layer of armourplas will be as effective against bullets and stabbing weapons as 0.5cm of steel but for a half of the weight. Against laser weapons (who are much more effective against steel based armour) 1cm of armourplas will be as effective as 2cm of steel. Many Imperial Guard issue uniforms contain thin 5mm) layers of armourplas covering the core body areas as protection against shrapnel (5mm of armourplas will only stop the lighter stub-gun and autopistol rounds).

Plasteel is a special type of armour made by layering steel and armourplas together. This has been found to offer a much increased level of protection compared to both materials individually. Optimum protection comes from using (by thickness) 1 part steel to 4 parts armourplas, the most effective armour being made of multiples layers of 1mm thick steel and 4mm thick armourplas. A 1cm thick layer of plasteel of this ratio has shown to be as effective at stopping kinetic round as 1.5cm of plate steel or 3cm of armourplas yet has only around 50% more mass than 1cm of armourplas.

Many ‘high end’ infantry armours have a body made of plasteel, a carapace of 1cm thick plasteel is capable of stopping 10mm autogun ammunition at short ranges (though multiple hits will cause the armour to fail) and can protect the user from dozens of direct lasgun hits, whilst still being light enough to wear comfortable for extended periods of time. Guard Storm Troopers have also reported that plasteel carapace armour has, one some occasions, saved them from direct boltgun hit (though this may be due to incorrect fusing in the bolt round itself, several used carapace suits were shown with considerable holes blasted through tem, the explosive fore of the bolt destroying the armour rather than detonating inside the targets torso).

Adamantium.

Adamantium is, in many ways, the premium material for use in armour. In terms of strength, toughness and mass it is vastly superior to steel and it is nearly impossible to destroy using conventional laser, plasma and melta weaponry. Unfortunately it’s scarcity, cost and complexity to manufacture limit its use to only the most important armour systems.

Adamantium Ore is one of the most valued commodities in the Imperium, so much so that all known sources of Adamantium ore are run directly the Imperial Guard (they are never contracted out to other sources) and shipments of refined ore are transported in Navy warships rather than on conventional transport vessels. The scarcity of ore and the difficulties in mining it mean that an iron ore quarry will produce, per labourer, between 50 and 80 times the mass of usable ore compared to an adamantium mine.

One the ore has been removed from the ground and pre-processed to remove the surrounding rock and most of the impurities found with it, it must be transported to one of the few places that can process the ore and then manufacture the metal. All of these sites are located on Forge Worlds around the Imperium, no other organisations have the technology needed to produce Adamantium items. At the Forge World, after a length ritual blessing, the ore will be further refined then superheated to create fluidic Adamantium. This process is incredibly complex and requires vast amounts of energy which have to be focussed into a very small area. The fluidic Adamantium is then allowed to cool slowly. At specific times in the cooling process certain other elements will be added to the metal to affect the structure of the Adamantium atoms. It is known that trace amounts of both tungsten and carbon-60 are added, but in what amounts and with what other materials remains unknown.

As only the Forge Worlds have the capability to produce Adamantium, and their output is relatively low, its use is very limited. The core frame of Power Armour is made from Adamantium and accounts for nearly 25% of the value of the suit. Terminator armour contains even more, with the main frame being thicker adamantium rods and some of the armour plates contain a sheet of adamntium along with plasteel and ceramite. The pilot and core systems in a Space Marine Dreadnought are all protected by plate Adamantium, making it tougher to kill than many battle tanks of a much greater size.

Titans make extensive use of Adamantium, their skeleton being made almost exclusively from it and with large amounts being used in its armour and plasma reactor housing. This makes many parts of the titan nearly indestructible; although it is possible to ‘destroy’ a Titan, either by crippling it or breaking all of its primary systems, even in the case of a catastrophic reactor breach the adamantium skeleton and reactor housings will normally survive with minimum damage, allowing the titan to be rebuilt later.

Some Imperial warships have armoured prows made of Adamantium, often many meters thick. The amount of Adamantium is inconceivably large and beyond the scope of the Imperium in the 41st millennium. It stands testament to the technology before the age of strife that this much Adamantium could be mined and produced and then used in a single warship. These Adamantium prows are nigh on indestructible and no effort will be spared in recovering them from ships lost in combat. The only source of new prows is from undiscovered wrecks or Space Hulks (which have been known to contain parts from ships predating the Age of Strife). The recovery of Adamantium Prows (along with the quest for STC data) is one of the primary reasons for the search and recovery of Space Hulks, even with the obvious danger those missions entail.

Adamantium offers superb armour protections. A 1cm plate will weigh 20% less than the same thickness of steel but render the target invulnerable to almost all man portable weapons. Used in smaller amounts Adamantium can massively increase the protection offered by other armour materials, as seen in Terminator armour. As explained above the use of Admantium as armour plate is very limited but even used in rods to provide the structure of armour is has a very interesting effect.

The most unusual, and possibly most useful, property of Adamantium is its ability to destabilize a disruption field (as used in power weapons). The atomic structure of adamantium causes the field to twist perpendicular to itself meaning that it softens the material in a direction away from the force of the attack. This means that although a stabbing attack may pass cleanly through power armour is a powerful disruption field us used, the adamantium rods prove very effective is stopping cleaving attacks.

As a side note it is useful to know that there is a standing bounty for the recovery of adamantium. Any Imperial citizen (including military personnel) will be rewarded, in cash, for the recovery of adamantium scrap (which is then sent back to the Forge Worlds). It is also worth noting that the destruction of Imperial property for the purposes of the recovery of Adamantium is punishable by death of the perpetrator and all their family.

Flakboard.

Flakboard refers to sheets of armour material (normally armourplas with a steel wire support matrix) used to create temporary shelters or to reinforce the inside of bunkers. Flakboard is not meant to be used as direct armour (it provides good protection against small arms only) but instead it is to provide protection against shrapnel. Sheets of flakboard are often added to the insides of rockcrete fortifications to protect against ‘spalling’, shrapnel passing through the rockcrete or chips of rockcrete knocked off in an attack.

Rockcrete.

Rockcrete is very similar to the material often locally called ‘concrete’. It is made by mixing various grades of filler material (sand and gravel) with water and bonding agent (similar to traditional cement). A rapid dehydrator compound is added that quickly dries and cures the binding agent making most smaller structures (up to 0.5m thick) usable in less than 24 hours. Rockcrete can be made using almost any local material for filler but the binding agent is normally manufactured specially and brought in with the construction force.

Rockcrete structures are either made in sections off site then assembled on site. For larger structures the shape of the building must be made and the rockcrete poured into the mold. A skeletal structure of steel bars is included in the rockcrete for further strength.

Many larger buildings are available as quick form kits – a frame is premade using flackboard and steel bars. This can be quickly assembled and placed on foundations before the rockcrete is poured in. A team of 250 combat engineers can, using this method, create a level 3 fortification in less than 48 hours, large enough to house a regiment of guardsmen plus all the ancillary support it needs.