Investigation of wear resistance of oxide added al matrix composites produced by P/M method

In this study, 5% by weight, copper powder was mixed with aluminum powder and this mixture was used as the matrix component. Then, 5%, 10%, 15% ZrO2-Y2O3 powder was mixed into the Al-5%Cu matrix component as a reinforcement element. Powder metal samples were obtained by pressing the mixed powders unidirectionally with 300MPa pressure. Two samples were pressed from each percent powder mixture at two different sintering temperatures, 500 ºC and 600 ºC. Sintered samples were subjected to metallographic studies. Optical pictures and SEM images were taken, EDS and XRD analyses were done. Thereafter, microhardness and wear tests of the samples were carried out. According to the results obtained, the highest microhardness and the least wear loss were measured in Al-5%Cu sample sintered at 600 ºC. The microhardness value was expected to increase with the addition of ZrO2-Y2O3 oxide compound. However, the value decreased due to the increase in the pore amount. An increase in the microhardness value was observed as the amount of added ZrO2-Y2O3 powder increased from 5% to 15%. At 600 ºC sintering temperature, there were precipitations in microstructural examinations and microhardness increased accordingly. It is thought that the formation of precipitations in the grain increases the microhardness and causes a decrease in the amount of wear.