Dan
Tank
- Joined
- May 28, 2003
- Messages
- 4,186
- Reaction score
- 3
What is the most specialized, advanced piece of knowledge or skill you have? And if possible try your best to explain it to the rest of us? Things like advanced ray tracing algorithms, or how to catch a seal with your bare hands.
I am studying for some final exams right now. Some of the stuff we learn is pretty esoteric to a layperson. Like one method of predicting failure of ductile materials is the Tresca Criterion. What it states is that a material will fail if the maximum shear stress in any element exceeds one half the value of the yield strength of the material.
To understand it, you need to know that the shear stress is the amount of force applied over a certain area of material. The direction of the force is in the same plane as the concerned area. Shear stress doesn't only act on external surfaces, it can be evaluated for any arbitrary plane intersecting your object of interest. Even if you squeeze or stretch an object you are actually creating shear forces at 45 degree angles to the force you apply. And if you try twisting a piece of chalk you will see that it breaks in kind of a spiral angled at 45 degrees. That is because the shear stress is what's important for material failure.
Yield strength is just a tabulated property of a material. What it is exactly is the stress (force over area) required to begin plastically deforming a material. Most materials behave like perfect elastics as you start to apply stress to them. They bend or stretch and resist the stress with a proportional reaction force, and return to their original shape when you stop. But once you push a material past the yield strength, it starts to give away and it deforms permanently, like putty.
I am studying for some final exams right now. Some of the stuff we learn is pretty esoteric to a layperson. Like one method of predicting failure of ductile materials is the Tresca Criterion. What it states is that a material will fail if the maximum shear stress in any element exceeds one half the value of the yield strength of the material.
To understand it, you need to know that the shear stress is the amount of force applied over a certain area of material. The direction of the force is in the same plane as the concerned area. Shear stress doesn't only act on external surfaces, it can be evaluated for any arbitrary plane intersecting your object of interest. Even if you squeeze or stretch an object you are actually creating shear forces at 45 degree angles to the force you apply. And if you try twisting a piece of chalk you will see that it breaks in kind of a spiral angled at 45 degrees. That is because the shear stress is what's important for material failure.
Yield strength is just a tabulated property of a material. What it is exactly is the stress (force over area) required to begin plastically deforming a material. Most materials behave like perfect elastics as you start to apply stress to them. They bend or stretch and resist the stress with a proportional reaction force, and return to their original shape when you stop. But once you push a material past the yield strength, it starts to give away and it deforms permanently, like putty.
). I know a lot of people who can't do either worth shit. I think my diction is relatively advanced in comparison to the average person, sometimes to the point where people accuse me using a thesaurus to find "big words". Needless to say, it kind of flatters me.
