Aluminum and strength
leancrew.com
leancrew.com
In general, alloy design is an extremely high dimensional problem. You have composition, the forming processes, and heat treatments which all can profoundly affect the properties of the finished product. It's only since the fifties or so that we've really started to understand the internal structures of metals and how they affect properties like strength, and there are many open questions yet.
[1] http://link.springer.com/article/10.1007%2Fs11661-008-9593-3 [2] https://en.m.wikipedia.org/wiki/Precipitation_hardening
We probably spent as much time studying ferrous alloys as we did on Aluminium, Titanium, Copper and Nickel combined.
That said I suspect the reason is likely patent related. Metallurgy is not a new field but Aluminium alloying is relatively new wasn't really until after WW2. Alot of industrial research tends to be locked away behind patents.
General hardening is no problem. The challenge is when a company needs a very specific hardness. There is a fair amount of trial and error with the heat treater (at least at first) before they get it right.
The printout shows it, but is ~.08% off from 100%, which I assume is the Mg peak. But its a pretty big swing to go from no Tungsten to .106% Tungsten. I'm inclined to believe its a misread due to sandpaper or the coating (tungsten carbide coating on aluminum is very much a thing).
I know metallography is expensive, but its weird to me to have such cool gizmo for XRF and to have a lab do such analysis and not do something simple like hardness testing. That is cheap and fast. Well, fast anyway. I can't comment on lab larbor costs.
Instead of a lab, hitting up your local university materials lab for a grad student to do a quick hardness test and tensile testing would give very nice information and a basic guess as to type of material. XRD would also be more accurate than XRF I think, with proper preparation. Also, you would never test the cases as-is. The structural variable is small but important. A flat sample is better.
I'm sure there are other drawbacks as well. In fact the strength--which is seen as a benefit here--could be a drawback in a different application.
Typically you have material specific constraints (workability, cost, ease of sourcing) and application constraints (for a phone case this would be weight, stiffness, min/max dimensions things like that).
Once you have determined the constraints you can solve for the objective function using numerical methods i.e. Solve all the simultaneous equations.
That will identify the materials which are most suited to the chosen application. And will eliminate materials with drawbacks that cause them to fail to meet the constraints (so you don't end up with a iphone case made from diamond which costs a fortune or from ceramics which weigh a tonne).
Note to self: stop wearing caps that way before beard starts turning white.
If you follow him, he often includes a delightful amount of sarcasm and snark, enjoyably so.
I'm afraid you're making the mistake of confusing fashion trends with intrinsically appropriate clothing.
To illustrate the point, I'll use neck ties. Because suits and ties have been fashionable for many decades, they seem intrinsically fitting for the professional, but think of how silly it is, from a purely practical sense, to wear around your neck a ribbon made out of woven silk that is very difficult to tear.
(this post is very male-specific fyi)
If an adult wears a blue frilly onesie, a diaper, a frilly hat, and has a pacifier and a rattle, aren't they still dressing like an adult?
Yes. An adult baby.
I'm not confusing fashion with appropriate clothing. I'm saying that fashion is important, it's appropriate, and at a certain age, should be de rigueur.
The necktie is a more practical (and fashionable) version of the cravat. Like pants, wristwatches, sunglasses, rubber boots and cargo pants, the cravat and its baby cousins (the necktie & bowtie) come from military tradition post-17th century. It may have indeed been somewhat silly; nobody exactly knows what the original intent was. But if you had to wear something into battle in the 16th century, it might as well help protect your neck from spear glancing blows.
OK, so it's impractical. A lot of the crap we do is impractical. But that's not to say our impractical crap isn't important.
Why do we wear clothes? Sure, in the winter they're super important, but in summer? We go to the beach and wear practically nothing. Why not wear practically nothing all summer?
The biological anthropologist will tell you we've evolved to need clothes, whether it's preventing an open displaying of our genitals all the time, to reduce sexual signalling either when partnered or non-partnered, to obscure potential differences or weaknesses, and because we have no fur. The sociocultural anthropologist will tell you it's for protection, to present personal or cultural values, or for group bonding.
Whatever the reason, we do wear clothes. A loincloth or tunic (or kilt!) would probably be the most practical thing you could wear, and yet, here we are with cotton t-shirts and jeans and canvas shoes. What's the deal?
Fashion is basically the result of a culture coming together and deciding that for one reason or another, this is how we're going to represent ourselves while we hide our bodies both from each other and from the elements. And as you can imagine, there is always some versatility in how this gets represented. Usually, the rich man will adopt an expensive taste, while the poor man reaches for practical.
Up until 40ish years ago, we all still agreed on the same uniform - suits, buttoned collared shirts, leather shoes, felted hats, ties. But a gigantic cultural explosion happened and suddenly people were spinning their own clothes and coloring them like it was little home on the prairie on acid, and it spread around the world quite a bit, but not quite like here at home.
When you travel you will discover that there's still an appropriate fashion for different cultures. But among all the modern subcultures, it makes the least sense to me that computer nerds - who make decent money and are usually well educated - choose clothes without much thought for its quality or purpose, or even how it should fit.
Good fashion costs money. It costs money because it's actually quite laborious to develop good quality garments. And while you don't need good quality garments, they reflect your understanding of these things you cover yourself with every day, and they represent you as a person. You wouldn't want the representation of you to be cheap and ill-fitting, would you?
Great-fitting clothes make you look fantastic. And clothes made in a certain style, or to a certain degree of quality, not only express your individuality, they express your interest in and knowledge of fine things. Meaning you are smart, you are interesting, and above all, you care how you represent yourself to the world.
As you get older you should be interested in all the details of life. Put down the Taco Bell and learn what real mexican food tastes like. Put down the rum&coke and try some good scotch. Turn off the Cee Lo Green and turn on Miles Davis. And put down the t-shirt and cargo pants and find yourself some adult "professional" clothes that not only do you enjoy, but also present a sharp, educated, mature picture to others.
You could slap on a loincloth and get on with your day; it's not like people treat you completely differently based on how you present yourself. And I can totally see how having an interest in culture could take away from coding time. But as an adult, I have found it more rewarding to learn about and choose clothes that match my personal style while also making me look better.
And if nothing else i've said makes a difference: a tailored suit, good shoes, a crisp shirt and yes, a necktie, will probably get you laid, purely due to the fact that most men don't know how to dress anymore.
Unless you don't come near many people who think your way, then the look of clothes doesn't mean much. After all, it is a bit superficial and underneath those clothes we ware roughly the same.
Your whole story is based on certain standards you have, which you acquired during the years because of local culture, how you were raised, which people you see and so on. You value clothes and the look of it. That's ok. I value clothes mainly for their function, how long they last, looks of it come second. If it doesn't feel good I simply don't wear it. That's also ok. I also happen to know and frequent mostly people who think that way. Again, due to culture, how I was raised etc. So while in your eyes we might look like a bunch of schmucks, in truth we are no different, we have the same type of jobs and so on.
they express your interest in and knowledge of fine things. Meaning you are smart, you are interesting
Not quite. Just like people who are not well dressed can be smart and interesting, being well dressed doesn't at all epress a one to one relationship with how smart or interesting you are. There are enough people who look well dressed but just because they copied a look from a magazine or because they had someone pick clothes for them. In which case they look the same, but in reality they don't care about how the clothes fit or what they are made of, and they are smart nor interesting.
Underneath the layers of color on a Matisse, it's all just canvas. And the paint itself is superficial. But jesus, there's so much in that painting if you know how to look at it. (Ironically, Matisse did not fit in with the artist crowd of the time in Montparnasse because his dress and habits were incredibly boring and regular, yet everyone thought of him as the "wild man" from his use of color)
Admittedly, I've turned my baseball cap around backwards once in a while but it wasn't to look cool. (The brim of a baseball cap interferes with a rifle scope for example.)
[1] https://www.youtube.com/watch?v=mVPku-xItv8 [2] https://www.youtube.com/watch?v=sggbV7j_rLA