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[–] belrial 0 points 2 points (+2|-0) ago 

https://www.google.com/search?q=galvanic+series&rlz=1CDGOYI_enUS788US789&oq=galvanic+series&aqs=chrome..69i57.7447j0j4&hl=en-US&sourceid=chrome-mobile&ie=UTF-8#imgrc=eE-SNbe_TuISJM:

This is called the galvanic series. The higher the metal on this chart, the more anodic, and the higher its propensity for corrosion. Galvanic corrosion occurs when any two dissimilar metals come into contact in the presence of an electrolyte. In a lot of cases dissimilarities in the metal itself can set up galvanic cells. Finest example of this is pitting corrosion on 7076-T6 aluminum that has not been otherwise treated or coated to prevent corrosion.

If you were to place gold foil on an aluminum block you could almost watch the corrosion occur in real time. When used in aircraft, Magnesium is usually carefully maintained and its coating is inspected regularly to prevent that forsaken metal from corroding.

https://www.slideshare.net/SheamaT/theories-of-corrosion-2

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[–] Commie_Meta 0 points 1 point (+1|-0) ago 

On the other hand, magnesium has been used a lot in portable computers with no problems. Galvanic corrosion is not a challenge in many uses.

I'm more worried about ductility and the fatigue limit. If somebody gave me a fancy magnesium bicycle, I would sell it and buy an aluminum bike.

The elephant in the room is tooling costs. Carbon fiber molds can be made by any CNC milling machine out of ... carbon fiber. The start-up costs are absurdly low. You can make a pilot run of a carbon fiber drone entirely using hand tools. Magnesium injection molds tend to be made from exotic steel alloys and cost $100k+. The tooling cost for the magnesium parts shown in the story could easily be half a million dollars.

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[–] belrial 0 points 1 point (+1|-0) ago 

Now you are talking from the position I never stood at. My job was to keep painted things painted, and shiny things shiny. The Navy and Air Force feels no shame paying 18k for an antenna probe that essentially is a long trumpet with no mouthpiece.