DRY SLIDING WEAR BEHAVIOUR OF STIR CAST LM 25/ZrO2 METAL MATRIX COMPOSITES

In the present study, an investigation into wear properties has been carried out to identify the influence of ZrO2 as the reinforcement material on the LM25 MMC composite. Aluminum LM25 is selected as the base material, and it is reinforced with varying proportions of 0, 3, 6, 9, 12 and 15% of zirconia (ZrO2) manufactured by stir casting. Six tensile test and wear test samples were prepared according to the ASTM B-557-M-94 and ASTM G99 standards. Then, the prepared samples were subjected to the wear test using a pin-on-disc wear tester by varying the parameters such as loads of 10 N, 20 N and 30 N and sliding distances of 1,000 m, 1,200 m and 1,400 m for various percentages of ZrO2 reinforcement composites, and corresponding wear losses were measured. The wear test results reveal that an increase in the percentage of ZrO2 decreases the wear loss. It is also found that an increase in load and sliding distances increases the wear loss and hence the low wear loss is obtained for the sample which contains 15% of ZrO2 and is subjected to a wear test load of 10 N at a 1000 m sliding distances. Finally, the wear test samples are subjected to the surface roughness test. The surface roughness test reveals that an increase in the percentage of ZrO2 enhances smoothness and decreases surface roughness.