Hardening mechanisms in Al-Sc alloys

The hardening mechanism in Al-Sc alloys with scandium content of 0.11 and 0.19 at% is studied. Applying theoretical results due to the yield stress and work hardening of two phase alloys as a function of volume fraction and precipitate particle size, it is shown that after ageing at above 300° C the Orowan mechanism operates in these alloys. Using the experimental results, the volume fraction and average radius of the precipitate particles are determined.