Static and cyclic creep behaviour of SiC whisker reinforced aluminium composite

Static and cyclic creep tests were carried out in tension at 573-673 K on a 20 vol.-%SiC whisker reinforced aluminium (Al/SiCw) composite. The Al/SiCw composite exhibited an appaient str ess exponent of 18.1-19.0 at 573-673 K and an apparent activation energy of 325 kJ mol(-1) for static creep, wher eas an apparent stress exponent of 19.6 at 623 K and an apparent activation energy of 376 kJ mol(-1) were observed for cyclic creep. A cyclic creep re tardation (CCR) behaviour was observed for the Al/SiCw composite. The stead y state creep rate for cyclic creep was three orders of magnitude lower tha n that for. static creep. Furthermore, the steady state creep I rates of th e composite tended to clear ease continuously with increasing percentage un loading amount. The static creep data of the Al/SiCw coinposite were ration alised by the substructure invariant model with a true stress exponent of 8 together with a threshold stress. The CCR behaviour can be explained by th e storage of anelastic strain delaying non-recoverable creep during the onl oad cycles.