Study On Semi-solid ZL101 Aluminum Alloy Preparation And Squeeze Casting Process

Semi solid metal forming technology has the advantages of short flow, good product performance and so on. It has broad application foreground. However, the semi solid forming technology is still at the starting stage, forming process is not yet mature and used less in the commercial application. Microstructural evolution during preparation by a serpentine channel and semi solid forming process were studied in the literature. It provides the basis for further research on the forming technology of semi solid ZL101 aluminum al oy.The influence of preparation process parameters on phase size and morphology of ZL101 aluminum alloy primary α-Al were studied, such as pouring temperature, the serpentine bends quantity, mould tempera ture, casting speed. Results show that, the blank with desired morphology of primary α-Al was obtained when pouring temperature is below 650℃. The size of primary α-Al decreases and the shape factor increases continuously with increasing the corners number. The size and shape factor of primary α-Al are 55μm and 0.72 respectively when the pouring temperature is 630℃, the curve number is 5. Semi solid billet with excellent performance can also be obtained with the decreasing of serpentine channel temperature and increasing pouring temperature. In addition, it is well controlled when the channel is not to be blocked and the production efficiency is improved. The quality of the billet is also affected by the casting speed. The possibility of gas involvement is increasing and the density of billet is reduced when it has high casting speed. The oxidation of billet increases with the air contaction improving. Comprehensive consideration, pouring speed is in the 0.5kg/s and the below.The preparation of semi solid b illet is the first step and the key of semi-solid forming. The quality of the blank is related to the formability, which affects the performance of the forming parts. The thixoforming process has a great influence on microstructure and properties of the formed parts. In this paper, the influence of specific pressure, die temperature and reheating process on the microstructure and properties of the casting was studied. Results show that, it can meet the formability when the billet was heated with resistance furnace. It is bad for increasing strength of casting with grain growth. So high frequency furnace is suitable to reheating process. The mold temperature and specific pressure have a great influence on mechanical properties of the castings. Excellent mechanical properties of the casting can be obtained when the specific pressure is 200 MPa and the mold temperature is 200℃. The tensile strength and elongation of the castings were 223 MPa and 7.8% respectively. The tensile strength and elongation of the castings were increased significantly with the heat treatment by T6. The tensile strength of the casting reaches 260 MPa and the elongation is 11.2%. The tensile strength and elongation of the casting were increased by more than 12% and 20%, respectively.