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Oh, I'm very much into Elm lately. I'm aware they're out there. It just took me a long time with Elm (and others) for me to articulate a _better_ reason why `Maybe` is useful.

I don't like the "experiment" either, but there are _always_ unintended consequences to actions. It's not my fault they're doing a crappy "experiment."

I agree... I wish we still had the prime character. But since Elm isn't at 1.x status yet, that earns me an "irritated smirk" rather than a table-flip. :)

1. Being ASD is not a carte blanche.

2. Suggesting that "simply knowing more" is sufficient ignores the way many men will discount a woman's knowledge compared to a man's knowledge simply because she's a woman.

3. Can we not resort to putting people into their place to establish dominance hierarchies? What about synergistic differences? Those are tremendously valuable.

4. Many meetups can be frustrating or downright hostile to women. Even well intentioned organizers can have a difficult time attracting women if attendance is already primarily male. Let's not forget that women make about 70¢ per $1 that men make, so they tend to have less opportunity to spend leisure time at a meetup.

This is a problem, and we can't ask women to simply try harder. They've been trying harder their whole lives. Perhaps it's time for us men to try harder for once.

The three main things to be concerned about are corrosion, galvanic corrosion[1] and galling[2].

Corrosion is more commonly known as rust, but that's technically reserved for steel (or, more accurately, iron) oxidation. Aluminum certainly corrodes, but it corrodes into aluminum oxide, or alumina, which is actually a ceramic that is stronger than aluminum. In fact, good luck using aluminum without a coating of alumina... it naturally occurs on the surface of atmospherically exposed aluminum. As a result, when a chunk of aluminum is broken off of a larger piece, the material almost immediately forms a protective layer of alumina. It's almost like aluminum self-heals in the presence of oxygen.

Galvanic corrosion occurs when dissimilar metals come into contact amidst an electrolyte solution. In the case of vehicles, that's usually seawater/sea-mist or salted winter roads. While saltwater is also responsible for accelerating normal corrosion, it also plays a part in galvanic corrosion. So yes, having aluminum and steel touching is a recipe for galvanic corrosion, but galvanic corrosion is not black-and-white. Each metal has an anodic index; a high or low anodic index doesn't matter all that much. What matters is the difference between the anodic indices of the touching metals. For aluminum and steel, that difference is quite small, so galvanic corrosion isn't a huge issue, but it's not negligible either.

Galling occurs when the sliding friction of two parts, say a screw and its threaded mate, results in plastic deformation, usually in the more ductile of the two pieces. This generally doesn't come into play in the construction of a vehicle because many parts are attached either by welding or by a bolt-nut combo. Choosing the correct materials for the bolts and nuts (basically, just use hardened, but not stainless, steel) gets rid of this concern in most cases. In cases where one must screw a steel fastener into a threaded aluminum piece, a helical insert is usually prescribed. While many manufacturers make these, we typically used Helicoil for spaceflight ops because they're tested and rated for spaceflight (batch traceability, proper composition docs, etc).

[1] https://en.wikipedia.org/wiki/Galvanic_corrosion

[2] https://en.wikipedia.org/wiki/Galling

Aerospace engineer here, weighing in...

I have two areas of expertise on this matter. First, I was on UW-Madison's competition-winning FutureTruck team about 10 years ago. We were, IIRC, the only team of about 15 other universities that replaced our competition car's (a Ford Excursion) entire frame with aluminum. In addition to replacing many other steel parts/assemblies with aluminum equivalents, we managed to bring the newly parallel hybrid SUV under stock weight... despite adding a large battery pack and motor. The thing I learned from this experience was: even though aluminum has about 1/3 the density of steel, your parts end up being about 50–55% of the steel weight because you need to add more aluminum to maintain equivalent strength. Basically, given the same tensile strength properties of a part, an aluminum one will be about half as heavy.

Second, I worked as a payload mechanical engineer for a number of spaceflight systems. Suffice to say, our base material for consideration was aluminum. Sure, we deferred to steel for certain applications (e.g., ball bearings, rat cage bars, fasteners, etc) and to myriad materials in others, aluminum was the standard. It has a tremendous strength/weight ratio, can be alloyed in many different ways to get different characteristics, is non-magnetic, is relatively cheap, and can have a number of interesting surface coatings applied. About the only major systemic problem aluminum has is that it is difficult to weld. Not impossible, as my FutureTruck experience tells me, but difficult. It didn't matter to us, though, since NASA generally frowns upon welded joints anyway. Too much strength variation due to heat stress and potential for FOD if not ground properly.

Anyway, I've been waiting for the auto industry to catch up to a bunch of college students for 10 years now. Nice to see one of the Big Four finally getting it. And cheers to the smaller car companies that have been doing it for years.