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Updated: 3 hours 24 min ago

I mentioned Andre in my

Sun, 2024-03-17 15:41

In reply to Monsieur Pineau, as I remember him

I mentioned Andre in my morning class of "Failure of Materials", when we wnt over some micromechanical fracture models. Speaking of him in the past was not easy. 

Fondly remembered André Pineau

Fri, 2024-03-08 05:41

In reply to Monsieur Pineau, as I remember him

Thank you very much Amine for sharing this post about André Pineau!
It is a very sad event... but Professor Pineau continues to live in our memories and inspire us!
I've prepared a small photo album with photos of André Pineau that I have.

Andre Pineau

Mon, 2024-03-04 09:32

In reply to Monsieur Pineau, as I remember him

Amine, your words about Andre are very touching and so true. It is difficult to imagine the field of mechanical metallurgy after him. I was profoundly marked by our discussions, even if we did not always agree scientifically. I had always wanted to initiate something with him, but we were both busy and now it is too late. There's a lot I could say but I would only repeat your words. We have lost a giant. My condolences to Joelle and her family and may Andre finallyt rest in peace in the kingdom of phase diagrams. I am sure that in Heaven, he will convince the residents of the benefits of the local approach which he pioneered and cherished dearly.

RIP

Mon, 2024-03-04 09:12

In reply to Monsieur Pineau, as I remember him

Dear Amine,

Thank you for your moving message, I will share it with colleagues. I did not have the chance of being one of his PhD students, but I was lucky enough that he found some interest in my research during my time at Centre des Matériaux, so we had many discussions over the years. He was and will remain one of the most inspiring person I've met. May he rest in peace.

conference

Sun, 2024-03-03 22:33

A moving eulogy

Sun, 2024-03-03 07:05

In reply to Monsieur Pineau, as I remember him

Dear Amine,

It is saddening to hear the passing of Professor Pineau. Your eulogy is inspiring. Thank you for sharing. 

 

Hi Mohammed, 

Mon, 2024-02-26 19:42

In reply to Young's Modulus vs.Tensile Strength Chart of Several Materials

Hi Mohammed, 

I wonder which figure you are referring to. Could you specify the number?

Best,

Juner

Young's Modulus vs.Tensile Strength Chart of Several Materials

Mon, 2024-02-26 17:21

In reply to Journal Club for February 2024: Mechanics in Solid-State Batteries: Mechanical Properties, Interfacial Failure, and Multiphysics Modeling

Dear Juner ZHU,

What are the References of the Young's Modulus vs.Tensile Strength E(σY) Chart of Metals, Alloys, Polymers, Elastomers, Ceramics and Glasses available on Google ?

Mohammed Lamine MOUSSAOUI

Dear Dov and co-authors, thank you for your comments.

Mon, 2024-02-26 13:30

In reply to Your questions

Dear Dov and co-authors, thank you for your comments. 

The quantum mechanical probability-based physics gives the probability of tunnelling based on a barrier's height and thickness. A low and thin barrier increases the possibility that wave properties interfere with the classical physics comprehension of matter. I don't know what levels are needed for the wave properties of matter to set in. However, I do know that the probability of tunnelling is increasing exponentially with decreasing height and thickness. With the barrier height, that is what it is, perhaps even a thickness on the atomic scale, which is what one normally connects to quantum mechanics, is still too big and far away from being close to allowing tunnelling. 

Regarding the kinks, thanks for the hint that the kinks are confined to the crack plane. I got that part now. I found the supplementary movie with the crack front and the interesting behaviour during growth. I can see that the crack front propagates by kinks that nucleate in pairs that repel each other and propagate along the crack front, towards opposite traction-free body surfaces. 

A comparison with sliding dislocations that we often see as a two-dimensional object is interesting. Also for dislocations, the motion is not a coordinated process but is instead repeated jumps that emerge from a single atom that takes the jump and then the closest neighbours follow. The dislocations are often compared with sidewinder snakes' way of motion. A difference is that the snake's modus operandi is that the kinks are running along the body from head to tail. The same could be possible also for cracks and dislocations if the kinks are initiated where the crack or dislocation meets a body surface. So many interesting details, thanks for an indeed interesting paper / Per

Re: Li penetration through solid electrolytes

Mon, 2024-02-05 19:37

In reply to Li penetration through solid electrolytes

Dear Ting,

Thank you for your kind words. Yes, Li penetration through SE is a very interesting mechanics problem. Direct experimental observations are actually limited due to the difficulty in testing, in situ, operando, or post-mortem. To our knowledge, the 2017 Electrochem. Acta paper by Jeff Sakamoto's team provided such an example: 

The electrolyte tested in their study is LLZO. 

Yet-Ming Chiang's group also has many direct observations: https://doi.org/10.1002/aenm.201701003. 

And also these ones for direct and in-direct observations. 

https://doi.org/10.1038/s41598-020-75456-0

https://doi.org/10.1002/aenm.202000702

https://doi.org/10.1002/adfm.202307998

Li penetration through solid electrolytes

Sun, 2024-02-04 13:39

In reply to Journal Club for February 2024: Mechanics in Solid-State Batteries: Mechanical Properties, Interfacial Failure, and Multiphysics Modeling

Dear Juner,

Thank you for leading the journal club discussion on the mechanics of solid-state batteries. The review your team provided is timely and insightful. I am very interested in the issue of Li penetration through solid electrolytes. You mentioned the possibility of Li penetration through grain boundaries of solid electrolytes. Is there direct experimental evidence of such penetration?

Best regards,

Ting

Dear Lixiang,

Fri, 2024-02-02 03:30

In reply to Constitutive theory for highly entangled hydrogels by considering the molecular friction

Dear Lixiang,

       Thank you for your question! I would like to clarify that the model prediction in Fig. 6b pertains to a fully swollen hydrogel with a high water content, whereas the prediction in Fig. 6c relates to a highly entangled hydrogel prepared with limited water content. Our model analysis indicates that the friction coefficient between chains and entanglements in these two distinct hydrogels varies significantly.

      In our understanding, water plays a crucial role in influencing the direct molecular interactions between the chains and entanglements. Additionally, the water content may impact the geometric configuration of entanglements and also that of chains, leading to further differences in behavior. I hope that this explanation addresses your query.

Best regards,

Bin

Question about hysteresis

Thu, 2024-02-01 14:05

In reply to Constitutive theory for highly entangled hydrogels by considering the molecular friction

Hello Dear,

 

It is very nice and interesting publication. I have a question for you. 

In Figure 6 b and c, the stress-stain curve is changed from no hysteresis to some hysteresis by changing the friction coefficient. Are there any more physical explainations for that?

 

Thank you,

Lixiang

Deadline is March 19, 20241.

Thu, 2024-02-01 11:40

In reply to Claim your travel awards for IMECE

Deadline is March 19, 2024
1. Go to 2024 IMECE® International Mechanical Engineering Congress & Exposition® (asme.org)
2. Click Submit Abstract
3. Select Paper Type: Government Agency Student Poster Presentation
4. Select Track: Government Agency Student Poster
5. Select Topics: 16-01 or 16-02. 

Deadlines have been extended

Tue, 2024-01-30 13:43

In reply to 2024 IEEE International Workshop on Metrology for Living Environment (IEEE MetroLivEnv 2024) Chqania 12-14 June 2024

Deadlines have been extended !!!

Last opportunity to propose minisymposia and plan your participation.

 

There is a tutorial

Mon, 2024-01-22 02:31

In reply to Modeling Nitinol

Abaqus tutorial to calibrate Nitinol material data test in Abaqus

https://en.banumusagr.com/abaqus-tutorial-plug-in-to-calibrate-nitinol/

 

Kind regards

Your questions

Wed, 2024-01-17 11:59

In reply to Discussion of fracture paper #39 - Dynamic Fracture on a Molecular Level

Dear Per,

First and foremost, thank you for selecting our paper to appear in the blog.

A reply to your questions: 

  1. Dislocation emission near a crack front in silicon crystal usually occurs first at about 900K. There is no dislocation emission at room temperature since the activation energy for dislocation emission at room temperature is much higher than the cleavage energy. The covalent bonds are responsible for the high activation energy for dislocation emission. This is regardless of the suggested kinks along the crack front. The kinks are always there, even when the theory of kinking is quite new. At room temperature, silicon crystal may be considered as an ideally brittle material.
  2. To answer this question (is the kink propagating under mixed mode closer to mode I or possibly closer to mode II?) we emphasize that kink motion, both kink advance and kink formation are planar entities in a 3D coordinate system. They propagate along the cleavage system (plane of propagation and direction of the crack front velocity, e.g., (110)[110] or (111)[112]); kink advances advancing parallel to the crack front, kink formations are generated normal to the crack front (by thermally activated processes). The boundary value problem is fully symmetric to the x-axis, the cleavage system is in the middle of the specimen and parallel to the specimen edges, where the deformation vector is normal to the edges. While the fracture surface is smooth at the scale of several nanometers (confocal optical microscope), scanning tunneling microscope (STM) scans show atomistic scale misalignment steps due to unavoidable misalignment between the maximum KI plane and the cleavage plane of the material. And yet no significant shear stresses exist to activate Mode II deformation.

    Dov Sherman

Bad drive link

Sun, 2024-01-07 22:20

In reply to Avoid 4th order tensors if you can

The google drive link in the parent comment is broken. Please use this one:

https://drive.google.com/file/d/0BzO5SDANDZyjQUVScDRTRnRleVk/view?usp=sh...

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