Post by tophattingson on Oct 10, 2016 2:26:38 GMT
Based upon testing the default 120mm cannon with different materials and barrel thicknesses, there are two outlier materials. This data is restricted only to my limited testing, so take "Best" with a huge grain of salt.
The best material for lowest weight is UHMWPE, due to it's high Yield Strength / Weight ratio.
The best material for lowest cost is Boron, due to it's high (Yield Strength / Weight) / Cost ratio.
Here's the full table.
There is a further complication, in that it is easier to reinforce, by increasing the width, the beam deflection stress (which the above materials fail to first) than from gas expansion strength. For instance, even 10m thick UHMWPE will shatter from sufficient Gas Expansion Stress, which Vanadium Chromium Steel will handle better.
Hence the third choice, the best material between 3.90 GPa and 5.17 GPa gas expansion stress is Vanadium Chromium Steel, simply because everything else breaks. I'm not sure if a gun with such high expansion stress is likely to be an efficient choice under any circumstance, but it's there.
There is a fourth choice that may be more efficient. In extremely rare and impractical conditions, as a result of slider constraints, the best material when 1mm of low yield strength material is sufficient is a lot more complicated. There are a number of potential choices, each of which optimises Mass and Cost in a different way. Additionally, depending on the exact requirements of the barrel to survive at 1mm, material selection becomes more complicated. Potential low density and low cost materials here are Selenium, Aluminium, Calcium, Cadmium, Magnesium, Zinc, Polyethylene and Lithium. I have yet to determine which of those are actually optimal.
