한국주조공학회

Hyper-eutectic Al-17.5wt%Si alloy bars of 25 mm in diameter were produced by horizontal continuous casting process. Effect of both casting speed and primary Si refiner (AlCuP) on microstructure and mechanical properties of the alloy have been investigated. With increasing a weight fraction of AlCuP, the average primary Si size decreased down to 20μм. On the contrary, there was no notable changes of microstructure and primary Si size according to the casting speed in the experimental range of this study, indicating that the cooling rate should be increased to optimize and refine microstructure and primary Si size. The experimental results including hardness, tensile strength and wear resistance tests of the processed alloy bars showed a good possibility to develop the high performance wear resistant Al-Si alloy.