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In this research, the corrosion effect has been investigated on the high-cycle fatigue lifetime and the fracture behavior for the heat-treated aluminum-matrix nano-clay-composite and piston aluminum alloys. For this objective, after fabricating stir-casted nano-clay-composite, standard samples were machined and rotary bending fatigue tests were performed. To study the corrosion effect, some specimens were corroded in in the 0.00235% H2SO4 solution after 200 hours and then, they were tested under cyclic bending loading. Due to increase in the hardness by adding nano-clay particles and the heat treatment, higher fatigue strength occurred, compared to the base material. Nano-clay particles shortened the fatigue lifetime; however, this effect was less in the corrosion-fatigue lifetime. Moreover, the failure mechanism was the brittle fracture behavior due to the observation of quasi-cleavage and cleavage marks.

In this research, the corrosion effect has been investigated on the high-cycle fatigue lifetime and the fracture behavior for the heat-treated aluminum-matrix nano-clay-composite and piston aluminum alloys. For this objective, after fabricating stir-casted nano-clay-composite, standard samples were machined and rotary bending fatigue tests were performed. To study the corrosion effect, some specimens were corroded in in the 0.00235% H 2 SO 4 solution after 200 hours and then, they were tested under cyclic bending loading. Due to increase in the hardness by adding nano-clay particles and the heat treatment, higher fatigue strength occurred, compared to the base material. Nano-clay particles shortened the fatigue lifetime; however, this effect was less in the corrosion-fatigue lifetime. Moreover, the failure mechanism was the brittle fracture behavior due to the observation of quasi-cleavage and cleavage marks.

In the presented article, the temperature effect was studied on creep properties and fracture behaviors of AlSi12Cu3Ni2MgFe aluminum-silicon alloys, unreinforced and reinforced with SiO2 nano-particles. For such objective, standard specimens were fabricated by gravity casting and stir-casting methods, for aluminum alloys and nano-composites, respectively. Then, force-controlled creep testing was performed on standard specimens at 250, 275 and 300°C, under 100 MPa. Then, to find failure mechanisms, the fracture surface of test samples was also analyzed by the field emission scanning electron microscopy. Experimental results depicted the temperature changed creep behaviors of both materials, effectively. Moreover, a significant improvement in creep properties was observed by reinforcing the aluminum matrix with nano-particles, besides a heat treatment process. Such an increase in the creep lifetime was higher at 300°C. In addition, the fracture surface investigation of both materials implied the same brittle behavior, with quasi-cleavage marks. The failure location changed from inside the intermetallic phase into boundaries of the intermetallic phase in the nano-composite.

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