عنوان مقاله [English]
The most important defect in casting of Al-5Cu-1Ag alloy is hot tear. To solve this problem, using new casting methods such as semi-solid casting process is in forth. In this research after alloying process, samples were casted via common direct casting (DC) and semisolid casting (SC) methods. These samples were aged for 18 hours at 150 °C. Microstructural studies were performed by optical and scanning electron microscopes equipped by EDS for elemental analysis and image analyzing by CLEMEX software. Mechanical properties were investigated by the use of Brinell hardness and tensile strength measurements results. Study on semi-solid behavior and determination of optimum solid fraction were performed by Thermo Calc Software. Results show that the dendritic structure in DC casted samples has changed to a 78% spherical structure with 48 μm diameter in SC method. Thus, hardness, tensile strength and elongation increased up to 50%, 20 % and 77 %, respectively. According to thermodynamically modelling results the optimum temperature range for rheocasting of Al-5Cu-1Ag alloy is 545-612 °C.