Monotonic and cyclic deformation behavior of a SiCw/6061Al composite at elevated temperature

Abstract

Thermo-mechanical fatigue (TMF) tests were conducted on the 15 and 28 vol.% SiCW/6061Al composites under temperature cycling between 150 and 300 °C and mechanical strain ranges of 0.004–0.012. The effects of temperature–load phase and volume fraction of SiC whiskers on the TMF behavior were examined. The results showed that cyclic softening occurred in both composites during out-of-phase (OP) and in-phase (IP) TMF. In both composites, tensile mean stress was generated during OP-TMF, whereas compressive mean stress was generated during IP-TMF. The 15% SiCW composite demonstrated a longer life than the 28% SiCW composite in the case of OP-TMF, however, in the case of IP-TMF the fatigue life curves of the two composites passed across each other, i.e. at small strain range level the life of the 15% SiCW composite was longer than that of 28% SiCW composite, while at large strain range level, the life of the former composite became shorter than that of the latter composite.