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700 600 500 400 300 200 100 0 -100 -200 -0.5 -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 Stress / MPa α misalignment energy in-plane strain energy total energy
d/b:   1.414   /Å
G:   46.2    GPa
ν:   0.3   
w/b:   0.79   

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The experimental value of iron for the Peierls stress is 112.5 MPa

The stress at the graph maximum (Peierls stress) is 51 MPa

The stress using \({\tau _P} = 2\pi \frac{{\Delta {U}}}{{{b^2}}}\) is 54 MPa

According to the Peierls Nabarro model, the maximum stress is \( {\tau _P} = \;3G ( - 2\pi \frac{w}{b}) \) = 5 GPa

Or in the simplified version, assuming w=b, the maximum stress is G/180 = 361 MPa