[Suggestions] - new materials + corrosion

[Tofiel]

Since you introduced gaskets, and zinc, my suggestion is to add a brass as an alloy of copper and zinc made in refinery. Main purpose of brass is to replace plastic and rubber gaskets, to get higher temperature resilience, and add a high pressure to pumps (double, which means full pipe capacity, or 2kg for mini pumps). Since there is deficiency of copper in Aqua it could be a good extra progress step for mid to late game.

The other thing that comes to me when I hear zinc is corrosion damage mechanic. Every metal machinery will get damage over time when submerged in:
- oxygen, or polluted oxygen (some very low, like 0.01%/cycle for steel);
- water (0.8%/cycle for steel);
- distilled (no germs) water or steam (no damage);
- polluted water (0.85%/cycle for steel);
- salt water (5%/cycle for steel);
- brine (8%/cycle for steel).
Of course, there is also corrosion damage from leaking nuclear waste.
I have added everywhere for steel because some different materials will have different resilience to corrosion, i.e. copper, brass, or aluminium will be resistant to corrosion - passivation layer stops damage at 99.5% (it is not new, but still good, you might be loosing some resources on repairs over time)
Totally rusted building turns into material in rust or equivalent in metal ore.
There is a solution for rust. A metal construction can be galvanised with one of metals: nickel, chromium (you would have to add this too), zinc. Galvanising require a mechanical engineer with a blow torch (5kg methane canister)  and some metal for galvanisation (i.e. 20kg). CO2 as side effect. Galvanisation cannot be done in liquids (build a dry dock for underwater pumps or turbines).
Galvanised construction instead of getting corrosion damage, it looses content of galvanised metal:
- zinc 1%/cycle;
- nickel 0.7%/cycle;
- chromium 0.4%/cycle.
After protection layer is gone, back to normal corrosion procedure.
Remember that if one of those metals is used for construction, it will eat away at the rate of corrosion (as damage reaches zero, no materials will remain, unlike copper, which will turn into copper ore).
Some materials will be more resistant to corrosion, some, like gold or iridium, totally immune.
That also makes a reason to make INOX. Stainless steel made of iron, chromium, and nickel will be immune to corrosion... unless in contact with chlorine or liquid chlorine, but INOX can't be galvanised.

One more thing: will the galena be needed for microchips and party phone? But that would require some recipe to create it in small amounts on planets without it.