i have a question. I understand everything about Young's Modulus but, when they say a material has for example 210000 N/mm^2 , what do they mean? that it can handle 210000N/mm^2 in the elastic region? and then it goes to the plastic?
Young's modulus, yield strength (the stress at which a material goes plastic) and ultimate strength (the stress at which a material fractures) all have the same units. So it doesn't make sense to say "a material has 210000 N/mm^2", without specifying which parameter we are talking about. 210 GPa is a typical Young's modulus value for steel, so it is likely that in this case the 210000 N/mm^2 is Young's modulus.
No - it means that the slope of this material's stress-strain curve in the elastic region is equal to 210000 N/mm^2. So for example for an applied stress of 210 MPa, we would get a strain of 0.1%.
@@whitelight32 no, it means that you need 210 GPa stress in material to deform it by 100%, of course it will fail because Young modulus is only appropriate (linear) in elastic range of the material. Simply saying, Young modulus is the number that helps you transform stresses to strains and vice versa but only in the elastic range of the material, for concrete it is 0,20% for compression, for reinforcing steel it is up to ~0.24% in tension
I get amazed at the wealth of information available to us now. It's fascinating how physics, one of the broadest subjects, is so widely accessible and easier to understand if explained by independent creators rather than by mainstream school teachers. Amazing video, btw!
This is a really great straight forward video. As a Metallurgist, this was a really good introduction. You explained it way better than my professors did. I don't wanna be that guy that tells you why your video is wrong. But around 5:30, you show that carbon replaces the iron atoms in your model. In reality, carbon goes in between the iron atoms in the interstitial space. This is hopefully a video that you could do in the future talking about until cells and Crystal structures. Keep up the good work!
Thank you for your kind comments Jon. You are of course correct about the interstitial nature of steel - my mistake. Hopefully the animation still illustrates the point without being too misleading. A video on unit cells would be really interesting - thanks for the idea!
@pyropulse As an engineer with quite some work experience i must say the following: The stuff with the atoms is nice and everything but it should have been left out of a beginners introduction video entirely. The only thing that has to stick in the head of an efficient engineer is that E is a material constant that represents the slope of sigma and epsilon and is different for different materials. It is also commonly used in combinations like EI and EA. For the advanced theoretical engineer the atom part is important of course ;)
@@a1mforthetop I don't think so, I am a high school student and I get way more intuition if I understand how things work at the atomic level and then use the non-descriptive formulae.
It feels sad that you have very less subscribers. But I must say the way you explain concepts is awesomeeeee..... Looking for many more concepts from you ....
This is a clear and comprehensible explanation. The sounds in this video are sooo pleasing and captions are perfectly timed. It is evident that you have really put an effort into making everything great. Thank you :)
I feel ya dude. Its tough finding the right information presented in the proper way sometimes. Thats why alot of people struggle with math. Its overly complicated by improper presentation.
Very useful and simple refresher. I had forgotten these stuff from my college days. I was doing some project with my driveway to eliminate lateral stress on a retaining wall thereby extending its life. I was stuck at a point. I could get the vertical stress figured out but horizontal is what mattered. This video refresher cleared everything and I am at completion of my project. Thank you for the educational videos.
Everything is great about this video, the explanation is top-notch supported by equally great animations and designs. This is the first video I am seeing on your channel. Looking forward to watching other videos and understanding my concepts better.
Bro the background music in disturbing the concentration. Please upload it with a smooth and lighter music like in your stress strain demonstration video. Thanks
I wish I had these videos before solids and egineering experinentation courses. Incredibly well done. Ill be sure to lead other people your way when they are introduced to these concepts.
Thank you so much bro I got an engineering final today this helped quite a bit as well as several of your other videos. You have for sure earned yourself a subscriber.
Really interesting video!!! It is really awesome how this topic can be so simple to explain in a video of less than 7 minute instead when you are at university class normally takes 1.5 hours
Thank you for your job , and I'm wondering If I could take some images from this video to put it in my thesis , if you don't mind cane you send me the resources to put it in the reference Thank you again
Just found your page tonight I find it interesting so far. I’m a dual ticket Red Seal Ironworker and Welder and I’ve performed tensile tests both in school and at work. What you covered is very informative but you could have added more about quenching and tempering and how much tensile strength it can add. How it increases brittleness and ductility. I had a weld test on mild steel with 7018 SMAW welding electrode(rated for 70000 psi per square inch) heated red hot and quenched immediately. It sheared at 138,000 psi on the tensile test which I found very interesting.
😭😭😭😭😭😭😭😭 TY..TYSM! U r an ultra pro legend! God bless u! Why don't u tutor our teachers as well..I don't get a single word in his lecture! I feel blessed to have u as my tutor...TYSM!
Yes. If you know the applied force (compressive or tensile testing), the cross-sectional area and the strain, you can calculate the Young's modulus. Hooke's law is the key word. In the beginning of this video he mentioned shear modulus and bulk modulus. For isotropic materials all of these moduli (Young's, shear, bulk) are related via Poisson's ratio. I think it would be a nice video topic (also maybe how it works in orthotropic materials). He did mention shear modulus in the video "Understanding Torsion", though.
Good video that I can recommend to my students. But be careful: in your stress-strain curve, you have greatly overestimated the elastic strain (it's just 0.1-0.5% for most steels) as compared to the plastic strains. Also, while many engineering materials indeed follow Hooke's law, this is by no means generic behaviour. Many plastics, foams, and biological matter are very different :-)
Great video. Wish it were a bit longer. I especially wanted to see a comparison of various materials, including graphene, which has the highest Young's modulus as far as we know.
@The Efficient Engineer You're quite welcome. It seems like I'm an earlycomer to your channel, meaning I'll probably get to talk to you one and one and my feedback will actually matter. Just the way I like it :)
Correction if I may. 5:37 depicts the Fe atoms being replaced by Carbon, that's what happens in substitutional alloys. Steel is a interstitial alloy, the carbon atoms to not replace Fe atoms, instead they reside in the space between the Fe atoms. This is VERY important since the formation of martensite depends on the position of those C atoms to change the crystal structure of steel into BCT(body centered tetragonal)
keep up the great work. Looks like you're channel is very new but your presentation and video making skills are already on par or better than quite a lot of educational content here on RU-vid. I'm going to pass this on to my material science professors as they would be great for freshman engineering students.
Every topic is very well explained and helps us visualise, which is really important. Hats off to @The Efficient Engineer. But it would be very much appreciated if music is not used.
Awesome video! Btw, just a question. So assuming that stiffness in polymeric material is caused by the intermolecular forces. So the stress-strain curve for polymeric materials flatter in higher stresses cause the molecules are farther apart and the intermolecular forces are weaker and less stress is required to pull the molecules apart. Is that right?
I have a question: If two materals have the same Young's modulus value, but different yield strengths, will the material with a higher yield strength be called more elastic than the one with a lower yield strength? Or is only the Young's modulus a measure of elasticity?
Awesome video! The explanation was brief and right into the point. Thanks a lot!! I was wondering what sort of software you use to make your videos. The transitions are smooth, and the figures and graphs are animated.
Great aninations and best teaching method....but the number of lectures are not enough to fulfill our courses..Hope that it get benifits to students in near future🥰
Hello The Efficient Engineer! Thank you for your videos! They are great! I have one question. Why did you show on graphic on 2:38 that wood (pependicular to grain) is stiffer than wood (parallel to grain). I think it must be contrary because if load direction is parallel to grain than grains are tensed by all their length. But if load is pependicular to grains, so only part of grain and the space between grains are strained. Isn't the second case lesss stiff than the first one?
Sir my doubt really got cleared. Thank you, sir. Sir, it would be better if you decrease the background music just a bit. yours faithfully Hriday Sahoo, India
Great video :) I have a question. In your opinion, is the young's modulus more important than the bending resistance in parquets? or is there a difference between them ? thanks
You did say that the higher the young's modulus of the material, the higher its stiffness but smaller elastic deformation. Mild-carbon steel has a higher E and smaller yield strength which is the opposite of the high-carbon steel. Does this mean, use mild steel in structural design? Thanks in advance for your reply.
4:14 Hey nice, dislocations! We need to know quite a bit about them for our geodynamics/microtectonics M.Sc. class, so I know how much more detailed all that can get. Sometimes a less stiff material can be still desired, considering (brittle) failure, right? I mean if that bridge goes from "oh, here it works to "oh, here it collapsed" in an instant, when that would be pretty bad. Also one must keep SLS and ULS in mind. There's one thing I didn't quite understand yet though. Most of the time you're talking about elastic and plastic deformation. What's with brittle deformation? Or is brittle "deformation" simply plastic deformation after the strain was too high? Will have to keep watching some youtube videos about brittle failure, as well as rheology models considering not only strain but also strain rate. I'm very grateful for your videos and visualizations!
At around 2:30, i hear wood and composites as an isotropic material. I somehow remember them to be orthotropic. Correct me if i am wrong. Nice videos: this one and others on this channel. I sometime stream them on TV as well. Thanks for putting such info in concise form. :)
I would calculate the movement about a plastic lever; so how much it move before the break. movement = constant * (yield strain * lenght^2 / thickness)
The rule of thumb that we used, for a safety factor, was 1/2 the yield stress. Though the value can be moved, we used this rule of thumb for almost every application.
At 5:10 why elastic deformation is GPa and ultimate tensile is MPa... When you extend an material in order of GPa for sure you go over MPa ... I miss something?
Ultimate strength is in MPA and Young's modulus in GPA because Young's modulus is theoretical and material would break before it reaches that point . Ultimate strength is the value where a material will fail
So good an explanation it was..... believe me your subscribers are gonna increase with the speed same as the speed of light......good luck.... and I'm a subscriber too......=)
Thanks a Lot for the Useful info, I Have a Question Please, in Car Plates Industry when we use the 1050 Aluminum Alloy, what Temper you suggest to be Used and what Mechanical Properties are the best to avoid Plastic deformation when applying the Plate Numbers Please. Thanks
wow fantastic explanation brother ....if you are reading this would you please take a time to clear my confusion on this? In the case of loading an object with stress we actually recover energy in the elastic region but let's say we have atoms bonded to eachother on an object/To break the bond we supply energy and the atoms are separated,where does that energy we supply go>I mean there is a bond energy and we break it does it mean that our energy is cancelled byy the bond energy producing net 0 or what?Same for magnets,when two large attracting magnets are to be brought far apart we apply a huge force and do work,does that work get cancelled by attraction of magnets or it goes somewhere?please help..thanks in advance
Hi sir, This video helped a lot. I am looking for a video in which I want to know what is proportionality and proportionality constant. Most of equations stats that one is proportional to other and therefore uses proportionality constant. I searched a lot for these but satisfied results are not obtained. Your videos are conceptual and satisfies me, so pls try to make a video on this 🙏🙏🙏
Very instructive video. Thanks a lot for sharing. I have one small remark regarding the position of the carbon atoms in the steel lattice. In the animation, it looks like they substitute for Fe atoms, while in reality they are present in the interstitials. Maybe this might confuse people. Besides that, I am wondering what the exact reason for the slightly lower modulus of the high carbon steel (vs the low carbon steel) is. I can imagine that the presence of interstitial carbon slightly modifies the equilibrium bond length/strength between two Fe atoms. I suppose that the average Fe-Fe bond length increases with increasing Carbon content. How is the Fe-Fe bond strength affected and how does this overall lead to a slightly lower modulus with increasing bond strength? Can we assume that the bond strength remains the same and the bond length increases so that the strength/strain ratio decreases with increasing carbon content? Thank you!
Thx for the great clip. I have to say, this short 10min clip is much better than my professor's 1hr lecture. I have a question, thou. Can we say that Young's modulus is a similar concept to 'spring constant'?
Sir, is young's modulus of a material changes with the orientation of that material ? or it remains same in all orientations of the body ? please let know the answer.
Hello, I have question, In many literatures mention if young modulus of Al 6061 T6 is 68900 N/mm2. Then I did tensile test with JIS Z2201 standard. why I got so much smaller value? only 5400 N/mm2. Please answer me. thank you
@@TheEfficientEngineer I used JIS Z2201 14B standard (arc test piece). The result is Ys=7662N elongation 2.43mm, UTS 8175N elongation 7.97mm. The curve is look like common ductile materials
On the note of bridges during the end, isn’t yield strength of the material also of importance when wanting to avoid deflection and/or an overall elastic behavior? Of course, a rubber bridge isn’t as beneficial and sturdy as a steel bridge, but wouldn’t using high yield strength steel would also cause problems with deflection?
