Re: [Wien] About material breaking

[Muhammad Sajjad]

Dear Oleg and Marks
Thank you for your quick reply. Sorry for late, I was away for two days.
@Oleg:
Yes I mean ultimate material strength. The sent paper is quite helping. In
FIG. 2., stress-strain curve is drawn. We know applied strain but how can
we measure stress (F/A). Ok A is known but What is F? Simply how to get
stress value?

On Thu, Nov 26, 2015 at 6:39 PM, Oleg Rubel  wrote:

> Do you mean the ultimate material strength when you refer to "breaking
> point”?
>
> Straightforward calculations (like this one
> http://arxiv.org/pdf/1303.7259v1.pdf) are possible, but the obtained
> result will be orders (!) of magnitude higher than any practical values.
> The reason is that it is hard to capture mechanisms of materials plasticity
> at such a small scale.
>
> Oleg
>
> > On Nov 26, 2015, at 02:35, Muhammad Sajjad  wrote:
> >
> > Dear All
> > Can we use WIEN2K fto know about breaking point of material?  I know to
> calculate phonon spectrum  (using phonopy) for the stability of material
> but not breaking. Also some information from elastic constant (like C11 =
> Young Mod.).
> >
> > --
> > Kind Regards
> > Muhammad Sajjad
> > Post Doctoral Fellow
> > KAUST, KSA.
> > ___
> > Wien mailing list
> > Wien@zeus.theochem.tuwien.ac.at
> > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> > SEARCH the MAILING-LIST at:
> http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
>
> ___
> Wien mailing list
> Wien@zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:
> http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
>



-- 
Kind Regards
Muhammad Sajjad
Post Doctoral Fellow
KAUST, KSA.
___
Wien mailing list
Wien@zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
SEARCH the MAILING-LIST at:  
http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html

Re: [Wien] About material breaking

[Oleg Rubel]

Do you mean the ultimate material strength when you refer to "breaking point”?

Straightforward calculations (like this one 
http://arxiv.org/pdf/1303.7259v1.pdf) are possible, but the obtained result 
will be orders (!) of magnitude higher than any practical values. The reason is 
that it is hard to capture mechanisms of materials plasticity at such a small 
scale.

Oleg

> On Nov 26, 2015, at 02:35, Muhammad Sajjad  wrote:
> 
> Dear All
> Can we use WIEN2K fto know about breaking point of material?  I know to 
> calculate phonon spectrum  (using phonopy) for the stability of material but 
> not breaking. Also some information from elastic constant (like C11 = Young 
> Mod.). 
> 
> -- 
> Kind Regards
> Muhammad Sajjad 
> Post Doctoral Fellow
> KAUST, KSA.
> ___
> Wien mailing list
> Wien@zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:  
> http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html

___
Wien mailing list
Wien@zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
SEARCH the MAILING-LIST at:  
http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html

Re: [Wien] About material breaking

[Laurence Marks]

Maybe it is appropriate to clarify this.

As a rule plasticity occurs via dislocation motion and/or nucleation. While
these can be modelled it is a complex calculation to obtain the needed
terms. If you are interested in this read up on terms such as Peierls
stresses, e.g. https://en.wikipedia.org/wiki/Peierls_stress

On Thu, Nov 26, 2015 at 9:39 AM, Oleg Rubel  wrote:

> Do you mean the ultimate material strength when you refer to "breaking
> point”?
>
> Straightforward calculations (like this one
> http://arxiv.org/pdf/1303.7259v1.pdf) are possible, but the obtained
> result will be orders (!) of magnitude higher than any practical values.
> The reason is that it is hard to capture mechanisms of materials plasticity
> at such a small scale.
>
> Oleg
>
> > On Nov 26, 2015, at 02:35, Muhammad Sajjad  wrote:
> >
> > Dear All
> > Can we use WIEN2K fto know about breaking point of material?  I know to
> calculate phonon spectrum  (using phonopy) for the stability of material
> but not breaking. Also some information from elastic constant (like C11 =
> Young Mod.).
> >
> > --
> > Kind Regards
> > Muhammad Sajjad
> > Post Doctoral Fellow
> > KAUST, KSA.
> > ___
> > Wien mailing list
> > Wien@zeus.theochem.tuwien.ac.at
> > http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> > SEARCH the MAILING-LIST at:
> http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
>
> ___
> Wien mailing list
> Wien@zeus.theochem.tuwien.ac.at
> http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
> SEARCH the MAILING-LIST at:
> http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html
>



-- 
Professor Laurence Marks
Department of Materials Science and Engineering
Northwestern University
www.numis.northwestern.edu
Corrosion in 4D: MURI4D.numis.northwestern.edu
Co-Editor, Acta Cryst A
"Research is to see what everybody else has seen, and to think what nobody
else has thought"
Albert Szent-Gyorgi
___
Wien mailing list
Wien@zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
SEARCH the MAILING-LIST at:  
http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html

[Wien] About material breaking

[Muhammad Sajjad]

Dear All
Can we use WIEN2K fto know about breaking point of material?  I know to
calculate phonon spectrum  (using phonopy) for the stability of material
but not breaking. Also some information from elastic constant (like C11 =
Young Mod.).

-- 
Kind Regards
Muhammad Sajjad
Post Doctoral Fellow
KAUST, KSA.
___
Wien mailing list
Wien@zeus.theochem.tuwien.ac.at
http://zeus.theochem.tuwien.ac.at/mailman/listinfo/wien
SEARCH the MAILING-LIST at:  
http://www.mail-archive.com/wien@zeus.theochem.tuwien.ac.at/index.html