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The design and optimisation of the runner and gating systems is a key factor involved in the die casting of high quality products. Poor gating designs can lead to various defects such as gas porosity, shrinkage porosity, flow lines, cold shuts and poor surface finish. CAE techniques are considered as the most cost-effective way in optimisation of the runner and gating design. A thin-walled magnesium telecommunication part was selected to be hot chamber die cast. Both computer aided design and numerical simulation techniques were applied for the optimisation of the runner and gating. The runner and gating system for the thin-walled part was designed with the aid of CASTFLOW. "Cast shots" were then simulated on a computer using a commercial software "MAGMAsoft" to numerically analyse the mould filling pattern. Die inserts were fabricated based on the simulation results. A series of casting experiments were conducted. The short shot filling tests proved that the simulation results matched the actual casting results very well. The castings were sectioned for microstructural examinations. Good quality thin-walled telecommunication parts with sound microstructure were produced.

Magnesium die casting has grown rapidly because of its excellent mechanical, electromagnetic and thermal properties, but it is still a trail and error process to design the gating system. In this paper, a commercial software package was used to simulate the filling process of die casting of a test bar. Two different gating systems were examined. It is shown from the simulation results that the melt fills the far end first and fills the rest of the part. The last filled sections are near the gates. No major difference was found between the filling processes of the two different gating systems. Compared with the experiment data of porosity level, it is shown that the porosity distribution in the final casting has a good agreement with that guessed by filling process.

Hot end is a key part of hot chamber die casting machine. In order to improve shot control and predict the life span of hot end parts, it is important to understand the melt flow and thermal conditions of the hot end in the furnace. A simulation program "VStar_HotEnd" using Finite Difference Method (FDM) is developed. The system consists of three modules: pre-processor, main-solver and post-processor. The pre-processor provides an interface with other CAD software such as Pro-E and AUTOCAD to convert three-dimensional geometric files in STL format into FDM mesh format. Thermal data for some typical materials and boundary conditions are collected in a library. The process of simulation is carried out by the main-solver after parameters are defined by the user. During the simulation the software allows the user to stop and watch the real-time position of melt front and the temperature distribution in the furnace. The post-processor makes it possible to display the simulation results with various points of view and sections and export the screen image to a printer. An example of using VStar_HotEnd to simulate the hot end of a die casting machine is provided.

Aluminum alloys, such as the 6082 alloy, is now becoming established for future lightweight vehicle structures, while Magnesium alloys remain a specialist material. By developing a low-cost, massproduction route for sheet magnesium, designers can start to explore the use of pressed magnesium panels into future vehicles. In this work, it is presented the feasibility study for an application and development of a hot forming technology to the forming an automotive external body (skin) panel. The reported forming trials of the front cowl panel were conducted using AA6082 and AZ31b alloys.

This study examined the microstructure and high temperature tensile properties of Mg-5Sn-3Al-1Zn-xCe (x=0, 0.5 and 1.0 wt.%) alloys. The alloys were melted in a steel crucible under a CO₂+SF₆ atmosphere and poured into a preheated permanent mold at 200°C. The microstructure of the Mg-5Sn-3Al-1Zn alloy consisted mainly of α-Mg, Mg₁₇Al₁₂ and Mg₂Sn phases. With increasing Ce content, an Al₁₁Ce₃ phase was newly formed on the grain boundaries. The results showed the tensile strength at room temperature decreased with increasing Ce content but increased at elevated temperatures.