Plastic Deformation

· The data for copper (o), aluminum (o), and steel (x) shown is compared to theoretical curves for the two yield mechanisms.
· The von Mises yield model is in better agreement with the data than the Tresca model.
· The data has been normalized by the tensile yield stress, σ_y, of the different materials and is plotted in terms of these parameters: (τ / σ_y) and (σ / σ_y).

From: Wyatt & Dew-Hughes,
"Metals, Ceramics & Polymers," Cambridge (1974)