Best material science teacher. GOD BLESS YOU, sir

A big thanks to you professor. I have cleared my exam just learning from your lectures ..thanks a lot and stay safe and healthy 🙏

Excellent. At least I figured out the confusing puzzles around me for two years through watching your videos.

These lectures are absolute wonder, with detailed explanation, which is even not mentioned in many famous books we study in bsc, 👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻👏🏻

nice lecture sir, your presentation was simple to understand and covered all points. Thank u sir

Great sir , hats of directly hitting the concept .

Sir the way you you teaching directly penetrate our heart🙏🙏,A thousand of thanks sir🙏May all lectures teaches like you🤔😶😞😞.

How I find the coordinates of another point on the dircetion in terms of a,b,c?

Nice explanation sir ji

why [001] does not represent transnational symmetry in tetragonal unit cell.?

@rajeshprasad101

5 жыл бұрын

[001] is a translational symmetry of the tetragonal crystal. But it is not symmetry equivalent to [001] and [010] directions. This can be seen in two ways: 1) The shortest translation along [001] is of length c whereas that along [100] 0r [010] is of length a. 2) [001] is the direction of unique 4-fols axis in the crystal. [100] or [010] do not have this symmetry.

I didn't get the second example sir

Thank you sir.

What is the Significance of the Miller Indices of Family of symmetry-related direction and Miller Indices of Family of symmetry-related plane ??

@introductiontomaterialsscience

3 жыл бұрын

All symmetry-related directions/planes have the same physical properties. For example all symmetry-related directions have the same Young's modulus.

@gouravjarwal2473

3 жыл бұрын

@@introductiontomaterialsscience sir please make videos on other topics of physics , your video are great and they contain concept unlike other teacher on KZread .

Sir, what is meant when you say these 4 directions only are Equivalent? How should I conceive equivalence ?

@introductiontomaterialsscience

3 жыл бұрын

The directions are symmetry equivalent. i.e.there is some symmetry operation of the crystal which takes one direction to the other. For example [100] and [001] in a cubic crystal because you can rotate [100] into [001] by 90 degrees around the four-fold-axis along [010]. In tetragonal crystal [010] is not a four-fold axis. So this rotation is not a symmetry rotation. Therefore in tetragonal crystal [100] and [001] are not equivalent, i.e., not sy,mmetry equivalent.

@thewhiteshirtmanoksh2163

3 жыл бұрын

@@introductiontomaterialsscience it's clear now, thanks to you sir.

how can i download class material?

If I take a different unitcell for the same lattice, will I get different miller indices?

@rajeshprasadlectures

2 жыл бұрын

Yes, Miller indices depend upon the chosen unit cell.

Sir in the second example the direction which u calculated as [1/2 1/2 1] ,I m getting it as [0 1/2 1] please check it again and tell me if I m wrong there.

@introductiontomaterialsscience

5 жыл бұрын

The problem is related to representing 3D on 2D. I am assuming that the direction goes from the corner to the top face centre. You are assuming that the direction is lying on the back face and going from the corner to the centre of the top edge. With your interpretation what you are getting is correct.

@kirankhan9544

5 жыл бұрын

Yes I also agree with u

miller indices for direction only represent the orientation of the direction and not its position or sense. So what do you mean by the sense of direction? In the video you did explain that sense means the positive and negative direction of a line about the origin, say it does not represent positive x-axis and negative x-axis, but in the latter part we learn that [100] is for +ve x-axis and [bar-1,00] as -ve x-axis direction. Please, somebody, clarify the meaning of orientation and the sense.

@rajeshprasad101

5 жыл бұрын

There are actually two approaches: to regard sense or to disregard it. If we disregard the sense then [100] and [-100] represent the same direction. If we regard sense, then of course, [100] and [-100] are opposite directions.

@rajkhandait8847

3 жыл бұрын

It depends on the choice of coordinate axis directions. For negative x axis, if you choose it as the coordinate axis direction, you can take miller indices as [100] instead of [bar1 0 0]

@rajkhandait8847

3 жыл бұрын

Both things are same in this case as it is one- dimensional. But if you would talk for [111] and [bar1 1 1] then both directions make the different sense surely. So here it makes the sense of using bar.

@dedication_355

Жыл бұрын

@@rajeshprasad101 sir ap technical

Sir in example no. 2 you take x as -1 and y as -1 but we said that mille indices in parallel direction have same indices so how this condition is satified in this case ?

@olasupo20

2 жыл бұрын

I didn't get it please

Thank You Sir

your videos are good....besides material science ...for other mechanical engineering related topics which videos i shall refer..Please reply

@embarrassed_dodo

3 жыл бұрын

Nptel is great source as whole mit ocw is a great source too

very nice explanation sir

Plz clarify the meaning.... orientation of line in this sense..?

Thanks professor

sir, i did not understand the example. why did u take 1/2 a , 1/2 b, and for c u took 1, how?? can u plz explain?

@rajeshprasad101

5 жыл бұрын

The OA vector is starting from the origin and going to the centre of the top face. 1/2 a +1/2 b brings one from the origin to the centre of the bottom face. then 1c takes us to the centre of the top face.

@purvakadwe6875

5 жыл бұрын

@@rajeshprasad101 thank u so much sir!!

thank you very much sir......

Awesome

Great sir

Thank so much sir ....🙏

Why z axis abset in tetragonal

Thank you Sir ❤️❤️❤️❤️

👍👍👍👍

ty sir

Thnku sir

Thanku sir

Ty sir

Thanks for fetching and eye holding lectures ,,,,the thing i wanna from you is that you complete the all aspects of metallurgy ,,,,for. ,,, accordingly Gate

hello please answer anyone to my question i.e why I need learn about these Miller or these lattices and unit cells simply about crystallography because these all are just imaginations where these Miller indices are to be used please give any one applications for my understanding purpose

@rajeshprasadlectures

3 жыл бұрын

Your question is indeed interesting. One of the most important applications of Miller indices is one of the most important devices that you and I using to communicate: the computers. As you know computer technology is based on Si wafers. And these Si wafers have to have specific crystal orientations (111) or (100). It is important to crystals of these specific orientations and then slice them in correct orientations. It is also important for further processing of wafer to make VLSI circuits. If (111) wafers are processed in an (100) line all the products will be a waste. You can check the following websites and videos: kzread.info/dash/bejne/e4ajq7qjqKzJcrQ.html kzread.info/dash/bejne/qIyfmLehoZqanrg.html www.tf.uni-kiel.de/matwis/amat/elmat_en/kap_5/illustr/i5_2_4.pdf You make me realize that I could have mentioned some applications like this in my video.

I didn't get it please

it will be 2 2 1 in second example..

ME 07