Physics-Based Flow Stress Model for Alloy 718

Abstract A dislocation density-based model for alloy 718 in the annealed state is proposed order to accurately describe deformation behavior of this a wide range thermo-mechanical loadings. The accounts numerous microstructural mechanisms, including strain hardening, grain size effect, dynamic aging (DSA), solid solution strengthening, as well phonon and electron drag which affects movements at high rates. Two types recovery mechanisms are also included: due glide associated with cross-slip screw dislocations. calibrated using experimentally determined stress–strain curves both low rates 10 –3 3 s −1 , temperatures 20 °C 800 °C. data computed good agreement experimental data. inclusion DSA found be effective combination corresponding observations. strengthening contribution increases decreasing temperature increasing rate. effect proves significant only rate (~ ).