Age hardening behaviour of 2014 Al alloy-SiC composites: Effect of porosity and strontium addition

摘要

The aging characteristics of 2014 aluminum alloy-SiC composites with and without strontium addition are studied and compared with that of 2014 Al-cenosphere syntactic foam (Al-Cenosphere composite) and 2014 alloy-SiC composite foam in order to examine the effect of strontium addition and porosity on aging behavior. It is observed that primary peak aging time of strontium added 2014 Al-SiC composite is same to that of 2014 Al-SiC composite. But, strontium added 2014 Al-SiC composite shows secondary ageing unlike that of 2014 Al-SiC composite. Again, 2014 Al-SiC composite foam and cenosphere added syntactic foam get peak aged almost at same time, But relatively at slower rate than dense composites. It is observed that the strontium added composite also showed a peak at 10 h for secondary hardening due to delayed precipitation of AlSr_3.