FINAL REPORT CREEP OF AU-4GI ALUMINUM ALLOY UNDER INCREMENTAL VARIATION IN STRESS

摘要

Incremental loading tests were performed on AU-4G1 aluminum alloy-sheet specimens subjected to tensile creep at 473 K. Tests consisted of changing the axial stress by a small amount, by either loading or unloading, during primary creep. Results were similar to those obtained previously on commercially pure aluminum. Incremental strain response due to a small increase in stress was essentially linear viscoelastic, while unloading caused cessation of creep straining for a time, following by linear visco¬elastic creep. Material stiffness increased during creep, indicating that strain hardening was taking place. For axial stress in the plastic range of the material, the modulus increased with time from an initial inelastic value and approached the elastic modulus.