The main ship building material of the HDC is Plastium. Its very formable at temperatures of over 60 degree, allowing small hull breaks to be repaired automatically after a short time. Its formed around a strengthened steel frame to not form while accelerating. A predecessor material is very helpful and gets its effect trough a combination of a very weak magnetic field, its own magnetic effects and its low melting point. It was originally invented to protect tires from breaking. Soon it was used in transportation to help and stop leaking water and oil tanks. After the rediscovery of space travel, the HDC soon discovered its potential for civilian vessels. Scientists needed to higher the melting point, so it isn't viscous at room temperature. This could be done by highly compressing it during the production.
The main material for armor is Fortistium, which is an alloy that is stronger than steel, but can resist Kinetic energy at a very high level, due to its higher flexibility and tear resistance, while also having a high melting point. It was rather discovered than developed. Like many great scientific discoveries, it was discovered by accident. During a hyperspace jump, a cruiser collided with an asteroid. It had some industrial materials of high value with it. As some ships later came to get those gods, they saw that during the crash some of the regular steel melted, along with the asteroid and created a weaker form of Fortistium. While trying to use drills to remove some parts and reach the high value materials, they noticed that the parts where the asteroid melted together with the ship were more resistant to damage. So they picked up a bit of the asteroid and brought it back home. Once analyzed, the Scientists began to make search equipment for the asteroid material and and trough experiments they brought it to near perfection.
Every dozen centimeters of Fortisium armor there is a centimeter of Caloris, an alloy that is extremely good at conducting heat. In a few seconds you can already measure the heat put on it a few hundreds of meters away. Its melting point is also very high, in fact so high, that it can only be made and than cut into the right pieces and not be poured into the right form. In bigger ships they also have integrated high duty cooling systems, which enable a atmospheric reentry without thrusters, if you can survive the actual landing. Its also very efficient against laser (real lasers, not star wars lasers) based weapons, but with overwhelming laser power it can still be cut, it just takes a while. It was developed over a long time. It needs some electricity to work. Originally scientists tried to develop superconductors that can even work at high temperatures. They noticed that if a certain amount of electricity is send trough a special alloy, the vibration of atoms is evenly distributed very quickly and efficient. This can be archived, because the electrons can travel nearly without resistance while also disturbing the heat. This effect takes more energy depending on the amount of heat.
One of the HDC's most explosive materials is Crepitum. Its energy density is very high and its explosions are have a high explosion power. It very stable, because it can only explode it is under slight electricity, pressure and a spark is given. To create this special material, HDC scientists used a strong AI and added all elements they had access to into it. After a few hours of trying, the AI came to a result. The result was a mixture of elements that has a high amount of potential energy that can be converted into chemical energy in a split second, if there is electricity and the density is high enough. This explosive material has a high potential, but the recources arent as easy to gather as other explosives, so others are still in use.
For its engines, HDC ships use their powerful reactors to create antimatter, that is used to bring the ship forwards. (note: there isn't such a thing as an antimatter storage, its all directly given to the engines).
