It's difficult to find good teachers in iit/ nit . Sir you are one of them 🙏
@nabinghosh44706 жыл бұрын
Excellent lectures...that's why its called an IIT ...Thank you very much sir😊😊😊
@SoumilSahu5 жыл бұрын
Prof. Rajesh is actually an exception among the "teachers" here. All the professors here are great engineers/scientists, but VERY FEW are great teachers.
@satwikpandey21805 жыл бұрын
@@SoumilSahu True indeed, Mr. Sahu :p
@yerkoc373 жыл бұрын
Thank you from Turkey 🇹🇷🇹🇷
@motiontv36213 жыл бұрын
Tell your Erdogan to not intervene in other countries matter.
@shubhamkumarsaw6851 Жыл бұрын
@@motiontv3621😂😂
@eylulZZ4 жыл бұрын
In HCP, sometimes prismatic plane (10-10) and pyramidal plane (10-11) also act as slip planes
@introductiontomaterialsscience4 жыл бұрын
You are right. The basal plane is the most important slip plane but not the only one.
@muhammadaftab57983 жыл бұрын
how to find that {111} have four plain and have 6 direction
@pijjj57422 жыл бұрын
Thank you for the lecture sir, you are helping so many students!
@vikashkumarvlogsnitj Жыл бұрын
i think sir, you are the best teacher of metallurgy.kaas app hamare college me hote
@IITian_shubham_shekhar_rajput3 жыл бұрын
Sir , in ccp why can't we take {110} as a slip planes...even these planes can be seen as a closely packed planes.
@praxii5 жыл бұрын
Is it possible for slipping and twinning to occur in the same grain?
@introductiontomaterialsscience5 жыл бұрын
It is possible.
@shivasmart9673 жыл бұрын
tq sir and education centr of iit delhi
@worldofengineeringknowledg11863 жыл бұрын
Excellent
@manojvelishala86335 жыл бұрын
Sir I found in some textbook that BCC has 48 slip systems, is that true?
@anuragsingh-lv2it5 жыл бұрын
Those slip system are not active slip system.
@introductiontomaterialsscience5 жыл бұрын
Please see reply to Abhishek Kumar.
@abhiseknayak60633 жыл бұрын
Sir I have a doubt that as we know in plastic deformation no internal crystal structure changes only unit cells slip over one another then isit possible every time that they are slipped only one direction if not then automatically crystal structure break because repeatation of unit cell will not be happened regularly?? Then what is happening there really??
@rajeshprasadlectures3 жыл бұрын
Not able to understand your question. Could you try to express it differently?
@lingamshravani68153 жыл бұрын
Then why bcc are brittle and the fcc are highly ductile in nature even though bcc has more slip systems(48) than the fcc(12) slip systems? Can you explain this question in terms of CRSS? sir
@GopalKrishna-rb8vv3 жыл бұрын
BCC have fewer atoms pert unit cell and their APF is low compared to FCC . Due to this , BCC don't have well defined slip systems (not having a truly closed packed plane) .This makes BCC more brittle
@AbhishekKumar-nr6dd5 жыл бұрын
In book, I have read that in bcc there are 48 slip system Can you please explain why so?
@introductiontomaterialsscience5 жыл бұрын
12 slip systems of type {110} are most favourable slip systems, i.e., they have lowest critical resolved shear stress (CRSS). However, in some bcc metals, like alpha-Fe, {112} and {123} slip systems have only slightly higher CRSS, and so are also counted as favourable slip system,. As there are 12 slip systems of type {112} and 24 of type {123} this brings the total number to be 48.
@physic01 Жыл бұрын
Sir pls suggest book or notes for this slip
@pankajojha50752 жыл бұрын
I have a question sir… Is it possible to have slip without dislocation?
@rajeshprasad1012 жыл бұрын
Well, theoretically it is possible, but will require very high stress. So practically, is always with help of dislocations.
@KuldeepSharma-pk6li5 жыл бұрын
Sir, there is no closed packed plane for BCC crystal structure then why are we considering {110} plane as a closed packed plane?
@introductiontomaterialsscience5 жыл бұрын
{110} is the closest possible plane in BCC, and it does have two close-packed directions in it (the two body diagonals of the type lying in it). Thus it is a good candidate for slip plane. However, in reality in BCC crystals the slip planes are not always {110} but the slip direction is almost always type. Thus a BCC crystal is found to slip on several planes containing the directions .
@prakharbhalla94613 жыл бұрын
Sir for hcp you gave 0001 as plane and 11-20 as direction. But if we take only the hexagonal P lattice then plane will be 001 but what will be the direction. Is it necessary to give slip plane and direction in the way you wrote or can it be given by considering hexagonal P lattice
@rajeshprasad1013 жыл бұрын
The issue here is not primitive vs. nonprimitive but three-index vs. four index.
@prakharbhalla94613 жыл бұрын
@@rajeshprasad101 but can't we give slip plane and slip direction for hcp with 3 index. Because for four index we are required to consider more than one unit cell
@viralgadhiya65504 жыл бұрын
why slip occur in closely packed plane and in closely packed direction??
@introductiontomaterialsscience4 жыл бұрын
The spacing between planes is inversely proportional to the atomic density within the plane. Thus close-packed planes are farthest apart. This weakens the bonding between the planes and so makes it easier for slip to happen. Slip happens by movement of dislocations. The dislocations create slip in the direction of their Burgers vector. Burgers vectors happen to be shortest lattice translations. Thus it is most likely to find shortest lattice translation and hence the Burgers vector in the close packed directions.
@viralgadhiya65504 жыл бұрын
@@introductiontomaterialsscience sir you write burger vector are smallest lattice translation.. Is it related to elastic energy store which increase with increase in burger vector and crystal try to minimize its energy. So burger vector is smallest lattice translation. I don't understand about why slip planes are closely packed planes. Can you have any video lecture on it??
@ravithakur00413 жыл бұрын
@@introductiontomaterialsscience Sir, can you please tell why spacing between planes is inversely proportional to the atomic density within the plane ? i.e. why closes packed planes are most widely spaced planes ? Also, I am getting confused with contradiction that interplanar spacing in case of (111) plane for FCC is lesser than that of (110) & (100) planes but despite of that why (111) is regarded as the most widely spaced plane ?
@ravithakur00413 жыл бұрын
@@viralgadhiya6550 Bro, it depends on planar density (no. of atoms per unit area). Just calculate this for respective slip plane, you will get to know. This is the answer for your last part question on why slip planes are closely packed planes.
@jidapa29692 жыл бұрын
Thank you sir.
@smarajitpunaykanti64633 жыл бұрын
Sir how are slip systems counted , is it by microscope .
@introductiontomaterialsscience3 жыл бұрын
By x-ray diffraction one knows the crystal structure. And by deformation experiments on single crystals one establishes the type of slip plane. Then one simply determines how many such planes are consistent with the crystal structure.
@haniabdulla24864 жыл бұрын
Can slip occur on a polycrystalline material or is it limited to only single crystal?
@introductiontomaterialsscience4 жыл бұрын
Yes. But the analysis becomes more difficult due to the presence of grain boundaries.
@haniabdulla24864 жыл бұрын
Introduction to Materials Science and Engineering thanks alot. Your lectures are very informative and helpful.
@sa35085nhs5 жыл бұрын
BUT BCC structure have 48 plane systems ????
@introductiontomaterialsscience5 жыл бұрын
Please see reply to Abhishek Kumar.
@ayay98354 жыл бұрын
Sir, can you please tell that what are topographically closed packed planes ??
@introductiontomaterialsscience4 жыл бұрын
??
@ayay98354 жыл бұрын
@@introductiontomaterialsscience Sir , this question was asked from me in an interview for phd. The exact question was : " Do you know about trophographically close packed planes in superalloys ? " Thats y, i asked you about the same . . .
@rajeshprasad1014 жыл бұрын
@@ayay9835 I really have no clue.
@ayay98354 жыл бұрын
@@rajeshprasad101 Thankyou for your time sir.
@krishraja98952 жыл бұрын
@@rajeshprasad101 I think the question was (or should have been) "topologically closed packed phases" (TCP phases such as Laves, sigma, etc.). The question was not relevant to the topic of this video!