SUPER IMPORTANT MSE NOTE

So im in mse lab; and this is apparently life changing

Stress strain Curve
Stress y axis - Stress = F/A
Strain = [L(f) - L(i)] / L(i)

the linear line is the elongation; once it hits the yield stress, permanent elogation/deformation
draw the area under the yield point, area under = elastic energy
-> makes a triangle 1/2 stress * strain

o - sigma
e - strain
E - youngs
U - elastic energy
p - density

1) o = F/A
2) e = delta L / L
3) U = 1/2 (o * e) not material property eg: e is not
4) o = E * e

Therefore
subbing 4) into 3)
U = 1/2 (o^2 / E) -> therefore introducing material property
MPI = o^2 / E

Then take Log of both sides

Log(E) = 2 Log(o) - Log(MPI)
And the slope is 2!

Want Lower E = Look for Materials below the line
Want Higher E = " " above the line

*didn't take mass into consideration; in the MPI equation.
If you want to take into consideration, just divide by density*

MPI = [o^2/E ]/ p = o^2/ [E*p]
MPI w/ density = (o/p)^2 / E*p

Basically go to properties -> advanced -> divide by whatever you are looking for eg: price, density etc.

2 types of stress
tensile + yield
Pick Yield Stress because any point on the curve can be called tensile strength, but since we are maximizing U, we have to maximize yield stress :)

Every material has their own yeild strength.

Taadaaah derived biioooattches!