An Investigation on the wear behavior of Al-(5-13)Si-Fe Alloys

The Effect of Fe addition (0.2-2wt%) on the wear behavior of Al-(5-13)Si alloys was investigated. The pin-on-disk wear tests were conducted at room temperature, under normal load of 45N, sliding speed of 0.13 m/s for sliding distance of 1000m. The results showed that bellow a critical Fe content (1.2wt% in this research), Si addition improved the wear resistance. In this regard, the wear rate of Al-13Si-0.8Fe alloy was observed to be less than 50% of Al-5Si-0.8Fe. This could be attributed to the fine distribution of hard AlFeSi platelets in interdendritic regions that increased the hardness and decreased the subsurface deformation and asperities adhesion. So, controlled delamination within tribolayer as well as abrasive wear could be proposed as the main wear mechanisms. Formation of large primary AlFeSi platelets at the iron content of more than critical value, however, facilitates the initiation and propagation of subsurface cracks and instability of tribolayer. This led to the higher delamination and abrasive wear with higher Si containing alloys.