# Yield stress vs critical load stress

1. Nov 28, 2016

### fonseh

1. The problem statement, all variables and given/known data
In Euler's theory , it's stated that the critical stress of beam is always larger than the yield stress of beam ...I dont really undertstand the differnce between them . Critical stress is defined as the stress that the mximum stress applied before the beam starts to buckle....

2. Relevant equations

3. The attempt at a solution
Does the yield stress here means the stress which the beam start to deform plastically ?
Why shouldnt the yield stress is smaller than the critical stress ?

When object is subjected to stress , the beam will deform plastically before it starts to bend and break .... So , i think that yield stress is smaller than the critical stress

Last edited: Nov 28, 2016
2. Dec 1, 2016

### PhanthomJay

Who told you that?

3. Dec 3, 2016

### fonseh

it's based on my understanding , correct me if I'm wrong

4. Dec 3, 2016

### PhanthomJay

Euler buckling applies to long columns where the critical buckling stress is less than the yield stress.

5. Dec 3, 2016

### fonseh

Do you mean for long column , the critical buckling stress is always less than the yield stress???