PSI - Issue 47

Robert Eriksson et al. / Procedia Structural Integrity 47 (2023) 227–237

237

R. Eriksson, A. Azeez / Structural Integrity Procedia 00 (2023) 000–000

11

˙ ϵ p

= ˙ γ sign( σ − q ) flowrule ˙ α = ˙ γ internal hardening variable ˙ q = ˙ γ H sign( σ − q ) back stress

(A.2) (A.3) (A.4) (A.5) (A.6)

f ≡ | σ − q | − ( Y + H K α ) ≤ 0 yield function / yield criterion ˙ γ ≥ 0 , f ≤ 0 , ˙ γ f = 0 , ˙ γ ˙ f = 0 Kuhn–Tucker conditions / consistency condition

where ϵ is total strain, ϵ e is elastic strain, ϵ p is plastic strain, ˙ γ is plastic flow rate, q is the back stress, H is the kinematic hardening modulus, α is an internal hardening variable, Y is the material’s yield strength and H K is the plastic modulus. The model is also given as pseudocode in Algorithm 1

References

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