Diamond Values

[LordXcano]

http://www.chm.bris.ac.uk/motm/diamond/diamprop.htm

I found this. While shear strength is what is normally used for fragmentation, there are absolutely no sources online I can find for this. The closest I found was shear strength at high temperature, so that doesn't count.

However, tensile strength is the point at which something breaks from it being pulled on. This is a fairly close analogue to fragmentation, so I feel like we could use that.

Compressive strength is what we use for pulverization, so that's fine too.

Proposals here are:

Diamond (Frag) - 1200 j/cc

Diamond (Pulv) - 110,00 j/cc

Keep in mind these are both low-ends, as the website shows that the values are very likely higher.

 

[CrossverseCrisis]

General Thread?

 

[LordXcano]

Where else would it go?

 

[LordXcano]

'''Bump.'''

 

[DontTalk]

I don't think we should be as inconsistent with such values as to use tensile strength instead of shear. That would lead to problems with every material were both is known.


On the compressive strength of diamond I have also found different values.

This article from the NASA seems to suggest 8.68-16.53 GPA.

Wikipedia lists 17 GPA, which is a bit higher. (though NASA seems a bit more relevant here, but I don't have the time currently to read the article of NASA to check which methods and assumptions are used)

Personally this values sound more realistic to me than a value that is halfway to atomization.

 

[LordXcano]

I think the problem is that I don't think there are any studies on shear strength of diamond. At least none I can find.

Given that Wikipedia and NASA have pretty similar values I would say that the website I linked is wrong and that 8680 J/cc is more correct.

 

[Lina_Shields]

Is this related to Cerebella's diamond feat? Generally we aren't going to see large chunks of diamond being smashed/pulverized in fiction.

Now regarding this topic, the issue with this is that there was no hints of the diamond itself being smashed into pieces, only that it started to form from the graphite being smashed. I don't think frag/pul. for diamond is the way to go here imo.

 

[LordXcano]

@Lina I don't know what feat you're talking about?

 

[Lina_Shields]

I thought that the diamond values needed based on this feat here .

Anyways, regarding your shear strength value for diamond, I am guessing that would be considered a fragmentation value?

 

[LordXcano]

Yeah, shear is generally fragmentation value.

 

[AidenBrooks999]

Well, I actually agree with this values

 

[Lina_Shields]

Well I guess this value is usable. However it's important to mention that instead of shear stress, compressive stress should be used since the force of the attack is being directly applied to the object itself.

So

• Fragmentation = 8890 j/cc

• Pulverization = 11000j/cc

Would these be correct?

 

[DontTalk]

I think the problem is that I don't think there are any studies on shear strength of diamond. At least none I can find.

Maybe, but the difference between tensile and shear is pretty large IMO.

Tensile could be more understood as the reverse process of compression, then shear.

The difference we are talking about is the difference between cutting a rope with a scissor and pulling so strong on both ends that it rips apart. The former is easy, the letter nigh impossible for a human.

In the end I rather have no value, than a bad one. As said, taking it like that kinda questions all existing ones, because we would gain alternative values for all of those if we would take it like that.

 

[LordXcano]

Why is shear strength used for fragmentation and compressive for pulverization anyway? Most feats aren't cutting feats, and punching, say, a 10 inch brick in half would be more compressive would it not?

 

[Lina_Shields]

I would think punching a brick would qualify more for compressive strength, since shear strength is basically applied when cutting objects.