tolerances mechanical properties materials

[stef_design]

Hey, guys, I have a curiosity.
in the definition of the main mechanical characteristics of a material, there is a tolerance with here then I use these values in my fem analysis.

example:
if the data sheet of a material put module el.=2900 mpa and snerv.=62 mpa, what tolerance do I have in those 2900 or 62 mpa?

Thank you.

 

[stef_design]

I don't know if it's inherent to this speech but I've found contrasting values with the famous compression set tires.
compression set is the ability that has an elastomer to return to the initial measurement/form under the action of a load. is measured in %.
in the date sheet of a rubber I had a compression set of 10%. I therefore dimensioned everything by following 10%.
Actually the supplier tells me that this 10% has a tolerance of +20%.

How do I rule? from here doubt: can I extend this problem to all mechanical characteristics of a material?

Hi.

 

[PierArg]

I don't know if it's inherent to this speech but I've found contrasting values with the famous compression set tires.
compression set is the ability that has an elastomer to return to the initial measurement/form under the action of a load. is measured in %.
in the date sheet of a rubber I had a compression set of 10%. I therefore dimensioned everything by following 10%.
Actually the supplier tells me that this 10% has a tolerance of +20%.

How do I rule? from here doubt: can I extend this problem to all mechanical characteristics of a material?

Hi.

take it absolutely lightly (I hope someone corrects me) because I remember something like this:
the concept of tolerance on the resistance of a material, as well as the form of elasticity, does not make much sense.
If you do characterization tests on the same material you will see how the results are all different from others. the value that is "stabilized" by the various norms has already been "filtrated" because it depends, not only on the chemical composition (often variable) but also on the errors of measurement and uncertainties of the machinery used for testing.