Effect of process parameters on the hardness and wear properties of friction stir processed Al-Fe-Ni alloy

The effect of friction stir processing (FSP) was investigated on the microstructure and pin-on-disk dry sliding wear resistance of cast Al-۷Fe-۵Ni alloy. The Vickers micro-hardness was measured at the applied load of ۱۰۰۰ g for an indentation time of ۱۵ s. The wear tests were conducted at the applied pressures of ۱, ۲, and ۳ MPa, sliding distance of ۱۰۰۰ m, at room temperature. The microstructure of the samples was also investigated using an optical microscope (OM) and a scanning electron microscope (SEM) equipped with an energy dispersive spectroscopy (EDS). The results showed that FSP refined the microstructure and eliminated the casting-related defects. FSP also encouraged the formation of ultrafine equiaxed grains. The optimum results were obtained at the rotation speed of ۱۲۵۰ rpm and traverse speed of ۲۵ mm/min. The wear results also showed that applying FSP reduced the wearrate by ۲۱% and ۱۴۰% under the applied pressures of ۱ and ۳ MPa, respectively.

Keywords:

Al-Ni-Fe alloy , Friction stir processing , Mechanical properties , Wear , Microstructure