Creep behaviour at high temperatures of rapidly solidified Al-Fe-V-Si dispersion strengthened materials

摘要

Reserch on the high temperature creep behaviour in tension of a rapidly solidified Al-Fe-V-Si dispersion strengthened material has been conducted. The microstructure consists of a fine Al matrix embedding small round-shaped Al(12) (Fe, V)_3 Si and Al_(13(Fe, V)_4 dispecsoids. Grain sizes of about 0.5 #mu# m and dispersoid sizes about 50 nm were obsered. High temperature tensile test data are provided from 481 to 823 K at strain rates ranging from 2.5 .10~(-6) to 10~(-2) s~(-1). The experimental data exibited high apparent stress exponents and high activation energies. A new creep equation is developed to describe the creep behaviour of the studied dispersion strengthened material. THis equation is a generalisation of conventional slip creep equantions without the use of a threshold stress and can be also used to predict the behaviour of other similar materials.