Abstract
Creep damage of SiC particle reinforced A6061 aluminum alloy, with various volume fraction of particle SiCp/A6061 composite, has been studied. Unloading modulus was measured from the unloading stress-strain curve at arbitrary creep testing time, during creep test for the qualitative assessment of creep damage. Densimetric change of the composite was also investigated and found to be associated with microstructural aspect of debonding at matrix/particle interfaces and cracks within SiC particles. The unloading modulus decreased with increasing creep time and with decreasing change of density of the composite. Damage parameter was found to have good relative correlations to unloading modulus and creep strain. The damage parameter derived from unloading modulus was formulated by a unique equation as a function of creep strain independent of the volume fraction of SiC particle. It has been concluded that unloading modulus was applicable to quantitative assessment of the creep damage of SiCp/A6061 composite.
