Comment on genius

• Warl0k3@lemmy.world ⁨3⁩ ⁨days⁩ ago

  Oh, I love how rabbit-holey metallurgy can get. One of my favorite topics is the processes used to cool hardened gears that have to be ground. Keeping the temperatures below a certain point so that they don’t lose the temper is surprisingly difficult even with external flood cooling (or working fully submerged), so you wind up with insane looking profile cutters that have cooling lines built into them directly.

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  • Fedegenerate@lemmynsfw.com ⁨3⁩ ⁨days⁩ ago

    That cutter is fucking art. The blades we ran had a ceramic core. Then the wax mould over the ceramic. Lose the wax, cast, then beat the shit out of it till the ceramic comes out the blade, now there are cooling channels built into the cast. Complex geometries too.

    I was asking why the blades needed a ceramic coating before going into the turbine. Surely we could just heat treat the blades to whatever hardness required.

    I was then informed that inside turbines it’s so hot the Hydrocarbons split up to free Hydrogen ions and the left over. The ceramic is there because it’s a highly acidic environment.

    Actually that story is my go to “how to mentor story”. I asked why we coated the blades in ceramics. The engineer told me it was really hot in there and just waited for me to twig. I didn’t, then he said it was so hot hydrocarbons break up into free hydrogen and the rest, and then waited. Then I caught on, I have no doubt if I hadn’t then he would have said “free Hydrogen is the literal definition of an acid” and waited. Then “Acid eats metals like titanium alloys” wait. “Then Acid doesn’t eat ceramics” wait. I genuinely try to lead people to answers that way just because the way he made my dumbass feel like the smartest tool in the room. Actually, I asked why we pre finished the blades to near mirrors just to acid etch them dull again, and was told it was for the ceramic coating.

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