Run some tests and find out! In a quick test, a 500MW laser at 250km took 1:09 to defeat 2cm of aerogel on a missile, and 1:57 to defeat 1.4mm of aramid--but the aramid is about 2.5x the price. The other candidates to look at would be basalt and polytetrafouroemethelyne, but if none of their stats have changed my guess is that aerogel will win for cost effectiveness and aramid for mass effectiveness. Do note, however, that if people do start using wide-beam lasers to fight low-conductivity materials reflectivity, melting point, and specific heat become more important. That said, silica used to be so far beyond even aramid in mass effectiveness that just bringing it to the head of the pack is a huge balance change.
The missile guidance changes look like a lot of fun--the micromanagement involved in triggering the terminal boost (particularly when staggering them to avoid nuke chain fizzles) had put me off before, but this looks amazing.
By the way, I love the closest-approach and other detailed intercept information--no more studying alignment of trajectories on the map!
No, that is how fusion-boosted nukes work: the high-energy neutrons produced by fusion can be very effective at triggering fission (and the additional fissions produced then chain-react). Thus, even very small amounts of fusion fuel can dramatically improve the efficiency of fission.
Amorphous boron really does have amazing properties (it is what boron fibers are made from), but we do not have the ability to make nontrivial parts from it yet--we cannot make complex parts by chemical vapor deposition, it is not ductile at all, is essentially unmachinable (because of its high strength and brittleness), and I believe that casting it gives a suboptimal crystal structure. However, people are working on laser-controlled CVD 3d printing, which may give a practical pathway to near-arbitrary boron parts within 10-30 years.
Costs seem to be based on both atomic abundance and ease of manufacture, with the assumption that materials that can be used additively are easier to manufacture than materials (notably the fibers) that need separate creation/assembly steps or complex creation (magnetic metal glass, notably). This seems reasonable, although I think it is not always implemented consistently.
What costs most in a nuke is heavily dependent on how you make it. If you use a very small core with a lot of explosive (as was common before the 1.06 patch broke fusion bombs), of course the explosives are more expensive. Right now radioactive isotopes are the most expensive metals by an order of magnitude or two, which seems reasonable.
Diamond, however, seems plainly wrong--as a merely metastable crystal, it is very difficult to make it by any process. I think it is so cheap because of the high abundance of carbon, but I would think its manufacturing process would put it at least on the scale of magnetic metal glass.
Of curiosity, what are people seeing for packed armor versus the stock gunship? It seems that something (probably the 286mm coilgun) is still making it through my attempts rather quickly--I wonder if this is another case where high-velocity projectiles are much easier to stop because they take less to convince to turn into plasma.
That said, forcing your opponent to use low-velocity projectiles is a fairly substantial victory in itself, since it forces him to fight at closer ranges.
Cannot target the drone launch device because drones are usually launched on the strategic map so the carrier is not in play. My experience is that lasers are fairly ineffective against well-armored drones (e.g. 5-10cm of silica aerogel on the turret, thickened amorphous carbon radiators)--are 14 1MW lasers that much more effective than, say, 1 500MW laser? And rail guns versus drones is almost always a losing battle; they can hit you long before you can hit them effectively.
My recommendation would be more/larger nukes; you are looking to fry radiators more than the armor itself (which means you may need shots from multiple sides, depending on the extent of their redundancy.
Although to get that effect (or really any contribution from whatever does not directly hit) you are looking at speeds certainly less than 3km/s, and probably much less--plasma does not have much tensile strength.
My two sub-kilogram designs. I would probably use the uranium in a missile and the plutonium in a coilgun (since the armature materials are so expensive, you can save money by using a lighter, more expensive bomb and reducing the armature mass). But these really get hit hard by the weight of the remote control; the smallest I have actually used thus far is 1.54kg, 541t yield.
And you can reduce reactor dimensions further, and with enrichment proportion affecting cost you can make small NTRs cheaper. The 1kg minima for reactor components are annoying, but together these translate to a considerable boost.
I think it depends on what you are doing. If you can line up a direct hit, frags are undoubtedly more damaging; if you want to be able to chase a flare and still cripple the target (or take out a flight of drones), there is no substitute for a nuke.
The official fluff is that guns are cooled by radiation from their barrels. Given how much heat is being put into them and the amount they can radiate at their melting point I do not think it plausible, but it is easy to calculate...
You can get a more readable version in the in-game material properties section. N and K are the index of refraction and extinction coefficient; together they determine reflectance (along with some other derivative properties (see www.photonics.com/EDU/Handbook.aspx?AID=25501 for a more detailed explanation).
Silica aerogel has negligible reflectance at all wavelengths, at least in-game (unless the Refractive Index Spectrum listings are lying). Offhand I would go for the frequency with the best luminance if you expect to hold a steady aimpoint (turret sniping) and best output power if not. (Against armor with a high thermal conductivity you probably want best output power, but I have yet to find such an arrangement that really requires worry.)
The only big frequency/armor surprise I know of is that silver has terrible reflectance in UV, so you can hard-counter silver/diamond armor that way. But better would probably be rhenium (excellent melting point and decent broadband reflectance) or magnesium (excellent reflectance without the holes of aluminum and silver).
It seem that large nuke design is now trivial--everything hits the 50% fission efficiency hardcap, so you just dial in the mass of fissile material to achieve the smallest yield and otherwise optimize for weight/cost. Uranium is actually now very competitive--a minor mass penalty achieves a huge cost reduction vs. plutonium.
And if you do want to trade price for weight with plutonium, go for Pu-240; its lower spontaneous fission rate allows more compact sub-critical assemblies.
Uranium seems less attractive for very small warheads; they have less fissile material for their mass so the mass penalty is steeper and the cost benefit smaller.
Trying to push on cost savings, switching from Octogen seems mass-prohibitive in small warheads (and the difference is negligible in large warheads).
Edit: It turns out that fusion boosts can be useful for some configurations of larger bombs: this is a 1.27Mt yield without the boost. (Note the boron; this is a useful middle ground for when osmium is mass-prohibitive and you need more fusion boost than lithium can contain (i.e. more than zero). I have also had good results from UHMWPE, rather bizarrely.) Interestingly, you can make bombs out of depleted uranium, but the cost savings in fissile material are offset by the ridiculous quantities of fast explosive required.
Hmm well this is just guessing but maybe it's the maximum density during detonation? I am just guessing mind you as other wise it seems more than a little silly. Another thing though is that the whole nuke system could be trying to represent teller ulam type of thermonuclear weapons with the sliders. I only say this as they are definitely a real thing that are very much used in real life but it is something that is classified so the game wouldn't be able to do the math for a teller ulam design. But as teller ulam nukes are a thing it might be approximating what those type of weapons can do?
Maybe the Teller-Ulam thing. I'm not sure. I know the stock high-yield warhead uses the max boost possible, so it's clearly intentional.
As a side note, I wish that using DU or other fissionables as the tamper affected yield due to neutron flux. Right now, as far as I can tell, with pure fission and low-boost warheads you want the densest possible tamper (osmium) and with high-boost warheads you instead want the lightest possible tamper (lithium).
Of course, it might be that secondary fission is only a feature of two-stage warheads. I don't know.
That is part of it--U-238 only in response to a very high-energy neutron (1 MeV). Fission reactions produce few such neutrons, so tamper fission plays little role in pure-fission/boosted fission (where most of the fission-produced neutrons will be absorbed by the primary fission fuel). That said, there were designs (I think one was built, and none tested) for bombs with a much larger quantity of fusion fuel between the primary warhead and a DU tamper for the purpose of inducing fission in the tamper.
I think this is the static density, not the imploded density, just from how the total masses work out. And I think the "this is replicating Teller-Ulam" unsatisfying because we are achieving ~10x the yield:mass of real Teller-Ulam bombs (for a given mass).