Investigation of microstructure, mechanical and wear properties of nanocomposite Al-5%Cu/SiC produced by powder metallurgy method

This study investigated and compared mechanical and wear properties and microstructure of Al-5%Cu/SiC nanocomposites with 2، 4 and 8 weight percent of SiC. Powder metallurgy method was used to successfully fabricate the nanocomposites. After milling، the resulted powder was cold pressed into pellets at a pressure of 100 MPa. Then the samples were sintered at 590 °C for 1 hour in an argon atmosphere. Densitometry، hardness، compression and bending strength and wearing of pin on the disk tests were performed for all samples. The microstructure was examined by scanning electron microscopy (SEM) and optical microscopy. Phase analysis was conducted using XRD method. The sample with 4wt% of SiC had the maximum density and minimum porosity. However، the best compressive strength and bending strength results were obtained for samples with 0 and 2wt% SiC، respectively. In the wear resistance experiments، the proportion of the slope of the weight loss due to abrasion to distance travelled by the sample was 0. 039. In the nanocomposites studied there are some problems like unwetability and difference in thermal expansions between the matrix and the reinforcement; however، addition of up to 8wt% nano SiC can increase the hardness by 50%.