Thor's hammer was sliced in two by Perrikus, and it was smashed by the Destroyer. Uru isn't naturally as strong as Adamantium, but when it's enchancted, it's granted an additional aura of protection that makes it impossible to rend apart except by a force powerful enough to override the enchantment. So to someone who can't overcome Odin's enchantment, it may as well be Adamantium.The whole Cap's shield thing is really just semantics, it's probably not worth debating at length. It was created a long time before the term "Adamantium" was coined, and Adamantium was created in an effort to duplicate the metal that Cap's shield is made out of. So technically, while Cap's shield may contain some of the same things that eventually became Adamantium, it's really more that they're related than it is the inventor taking actual Adamantium and fusing it with Vibranium.
On the grand hierarchy of metal strength, Vibranium is actually pretty low. It's fairly soft, and is easily destroyed. In fact, it's actually UNSTABLE, and prone to exploding. It's claim to fame isn't how hard it is, but how it can destroy any metal (including Adamantium and perhaps even Cap's shield), and how it can stop the momentum of anything that impacts it. Also, how it interacts with sound.
All of the past Adamantium-bending feats have been basically retconned into "Secondary Adamantium", which is some lower grade quality adamantium. It's not nearly as hard as Adamantium. It's probably more on par with unenchanted Uru. I think there currently remain only two or three cases of True Adamantium damage that are unretconned, and most of those were at the hands of major cosmic beings.
Carbonadium is a more malleable form of Adamantium. It's pretty durable, somewhat less so than Secondary Adamantium, but still very strong. I've only seen it used a couple of times, and Omega Red is really the only major character to use it.
The Destroyer armor is made from, depending on the source, either an "unknown metal" or Rhinegold. But, like the Mjolnir, it's not the metal that makes it so impervous. It's the enchantments. The reason why the Destroyer armor is harder than Mjolnir is because it received enchantments from the patriarchs of every mystical pantheon. It would take a force able to override the combined might of all the godly pantheons to destroy the armor. That, for all intents in purposes, makes it more durable than any just about anything.
The Celestial armor is, and this sounds hard to believe, not that durable. Celestials themselves are amazingly durable, but their armor is really more clothing than anything else. It wasn't designed to be armor, and that's why it's been pierced by people like the Invisible Woman, Phoenix, and Thor.
So in terms of METALS, it's:
1. Cap's shield
2. True Adamantium
3. Uru
4. Secondary Adamantium
5. Rhinegold
6. Carbonadium
In terms of THINGS, it's:
1. Destroyer armor
2. Cap's shield
3. True Adamantium
4. Mjolnir
5. Uru
6. Celestial "Armor"
7. Secondary Adamantium
8. Rhinegold
9. Carbonadium
10. Diamond