Bitcoin is all about the edge cases and being fully informed, I don't think there is any overkill in the comment but perhaps you can tell me what you think is overkill?
What does erosion have to do with this that corrosion does not cover?
i agree about the edge cases but lets review your edge cases that you have been focusing on in your first post (corrosion, melting point, and you mentioned hard to machine which relates to hardness if we want to engrave physically and doesn't matter much if we want to laser-engrave)
keep in mind corrosion is a process, not a property.
Corrosion:when we talk about corrosion it is all about the environment, put simply there are two categories to watch: corrosion that is not influenced by any other process and corrosion that is influenced by another process, such as the presence of stresses or erosion (
Erosion being a wear process, in which surface damage is caused by the repeated application of high localised stresses)
since the wallet is going to be kept at home environment, lots of conditions like stress induced corrosion cracking are not relevant.
the only things that we have to think about are "Aqueous" and "atmospheric" Corrosion. so strictly speaking a carbon steel with a simple coating is going to do the trick.
melting pointagain room temperature and a case of possible fire to reach a temperature of as high as 1100°C which is still inside working temperature of steels.
> the hardness of these materials is what you should look for
hardness is good but as we see with tungsten being so brittle it isn't a end all be all. I agree that stamping on steel is the best for the common man, I update the Al part to reflect the potential melting point
you misunderstood the meaning of "brittle". a brittle metal is a metal that breaks catastrophically when it reaches the UTS point.
we are talking about a metal, so tungsten with a Yield strength ~ 1000 MPa (it is 500 ish for SS) needs a tremendous amount of power to be broken.
i am not saying use tungsten , just pointing out what brittle means
The titanium is actually only about 10% more expensive than the 316SS
you didn't say which alloy though.
you are intriguing me to buy one and do a quick XRD to find out