PSI - Issue 33

Mohammad Azadi et al. / Procedia Structural Integrity 33 (2021) 181–188 Azadi & Aroo / Structural Integrity Procedia 00 (2021) 000 – 000

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As it could be seen from obtained results in Fig. 1, the heat-treated nano-composite had higher fatigue lifetime, compared to the base material, especially for the low-cycle fatigue regime or under higher stress levels. However, only the addition of nano-particle to the aluminum matrix had a reverse effect and decrease the fatigue lifetime. Such trends could be also for the corrosion-fatigue lifetime of studied materials, from Fig. 2. Moreover, comparing results of Figs. 1 and 2 showed that the corrosion effect on the fatigue lifetime was negative and the degradation of the material performance occurred, either in different types of alloys. Under high stress levels and through the low-cycle fatigue regime, the corrosion-fatigue lifetime of aluminum-silicon alloys (reinforced with nano-particles and the heat treatment) increased, compared to that of aluminum-silicon alloys, as also claimed by Rezanezhad et al. (2021). For better understand of obtained results for fatigue and corrosion-fatigue phenomena, experimental data were again represented in Figs. 3, 4 and 5. These results were separated for the aluminum alloy, the material reinforced by nano-particles and the heat-treated nano-composite. In all cases, the corrosion-fatigue lifetime was less than the fatigue lifetime, as also reported by Guerin et al. (2015), Chen et al. (2018), Rodriguez et al. (2019) and Azadi et al. (2021).

Fig. 3. The curve of the stress versus the fatigue lifetime for the aluminum alloy.

Fig. 4. The curve of the stress versus the fatigue lifetime for the aluminum alloy, reinforced by nano-particles.