Özet:

In this study, A356 alloy powders were alloyed with different amounts of Nickel (Ni) by the mechanical alloying (MA) method. Microstructural investigations of A356/XNi alloys based on Ni content were performed with an optical microscope (OM) and scanning electron microscope (SEM), energy dispersive x-ray spectrometers (EDS). Mechanical properties of A356/Ni alloys were evaluated by density, macro hardness, and wear tests. The pre-alloyed A356/XNi alloys were tested via pin-on-disc type wear test apparatus at different loads and sliding distances. Eventually, it was determined that the rate of the Al-Ni and Al-Ni-Fe-containing intermetallic phases formed in the structure at the grain boundaries increased due to the increase in the amount of Ni in the characterization studies (OM, SEM, and EDS). It was determined that the macro hardness decreased by about 10% until the addition of 0.5% Ni but then increased by 23% with 2.0% Ni. In wear tests, the wear rate increases with the increase in wear load. The lowest wear at 10 N load was obtained in A356/2.0%Ni alloy, and the lowest wear at 20 N load was obtained in A356/0.25%Ni alloy. Remarkably, the wear amount becomes more stable with the addition of Ni, especially in wear tests.

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