High-temperature low-cycle fatigue behaviour of a cast Al-12Si-CuNiMg alloy

The low-cycle fatigue behaviour of a cast Al-12Si-CuNiMg alloy, with a high content of Si, is investigated at 200, 350 and 400 degrees C. The fatigue test results show that the alloy exhibits symmetrical hysteresis loops, moderate cyclic softening and higher fatigue resistance at higher temperature. The fracture surface analysis reveals that more tear ridges are formed at higher temperature, which strongly affect the fatigue resistance. Furthermore, evaluation of the material fatigue resistance using an energy-based Halford-Marrow model indicates that the material's ability to absorb and dissipate plastic strain energy is enhanced as temperature increases.