# Stress Concentration Factor – Theories of Elastic Failure – Strength of Materials

Hello friends here in this video we are going to see what is meant by stress concentration factor stress concentration factor here I’ll write the definition it is defined as the ratio of maximum stress which is present at a knot or a hole to the nominal stress at the same section now here I have written that stress concentration factor it is defined as the ratio of maximum stress which is present at a knot or a hole to the nominal stress at the same section for this we need a diagram now here in this diagram we have in not sure not or we can say a groove or it is also called as a hole now stress concentration factor it is defined as a ratio of maximum stress now at the knotch area goes on decreasing so area is minimum and as we know the relation that stress is inversely proportional to area so stress will be maximum where the area is minimum so at the notch the area is minimum stress concentration factor it is denoted by K suffix T and it is equal to maximum stress which is there at the notch to the to the nominal stress at the same section nominal section means the original section like for example if this member it has a diameter D then its original area will be PI by 4 d square so that becomes the nominal area and the stress at that section will be called as nominal stress and the value of stress will be less because the area is more so maximum stress upon nominal stress so here I can say that therefore value of case of XT depends upon the material and geometry of the part so in this video we have seen what is meant by stress concentration factor

## 10 comments on “Stress Concentration Factor – Theories of Elastic Failure – Strength of Materials”

1. Dhruv Maggu Post author

Respected Sir, Is stress concentration factor depends upon material????
if yes how and if no then it is function of which factors…..

2. Ekeeda Post author

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3. shiv kumar Post author

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4. NEETESH gupta Post author

As you said ratio of maximum and nominal at same section
That means both stresses at same section
But later you said nominal stress is stress at actual dia.
Why is it so ?

5. Shah Saud Post author

I think u r wrong here
Correct me if i am wrong
Nominal stress is the stress at the notch with the reduced area
And the maximum stress is the actual stress that we find on the notch this is why we use k stress concentration factor

6. Ekeeda Post author

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