On the High Temperature Creep Behavior of Two Rapidly Solidified Dispersion Strengthened Al-Fe-V-Si Materials

摘要

The high temperature creep behavior of two rolled Al-Fe-V-Si dispersion strengthened materials has been studied by means of tensile tests. The microstructure consisted of 16% and 36 % volume fraction of submicron dispersoids evenly distributed in the aluminum matrix. High apparent stress exponents from 10 to 38, and high apparent activation energies of up to 700 kJ/mol, were observed. A threshold stress - like creep behavior was never observed at any temperature. The creep data was analyzed using Rosier and Arzt's detachment creep model. The predictions at high temperatures from the model are not accurate, predicting higher creep rates and lower stress exponents than those experimentally measured. A modified version of the detachment creep equation is proposed for predicting the creep behavior of dispersion strengthened materials taking into account the constancy of the microstructure during deformation.