Experiment and Simulation of High Pressure Die Casting Using ADC12 Aluminium alloy for Porosity Defect Prediction

• Main Author: Mohd Rosli, Mohamad
• Format: Thesis
• Language: English
• Published: Universiti Malaysia Sarawak 2021
• Subjects: TJ Mechanical engineering and machinery
• Online Access: http://ir.unimas.my/id/eprint/36626/6/Mohd%20Rosli%20password.pdf; http://ir.unimas.my/id/eprint/36626/; https://doi.org/10.1007/978-981-13-8297-0
• Institution: Universiti Malaysia Sarawak

This research analysis was carried out in a manufacturer of domestic die casting for the automotive industry, manufacturing Power Steering Rack Housing aluminium alloy primarily for domestic and international markets. Defects in die casting caused by molten metal when it filling the mould are gas or air trapping porosity, and shrinkage porosity. However, the controls of casting flaws or defects were depending on the know-how of die casting experts, and it is also based on a trial and error of experimentation. Trial and error of experimentation usually required a longer pace plus a highly expensive price which finally results in high rejection rates. This research present numerical simulations which analysed the molten ADC12 aluminium alloy filling flow, metal solidification behaviour and a predicted porosity over transformation during the heat transmission process from liquidus condition to solidus condition by using a 3-D numerical simulation on a computer. The numerical simulation recreated the real parameter setting conditions on the die casting unit, the mould gates design, the runner, the air vents, and the mould cooling system. The numerical findings are confirmed throughout assessments with the experimental casting result investigation. Results suggested a noteworthy assurance in the ability to predict porosity by casting numeric simulation. A shrinkage porosity position is precisely determined by significant correlations between numerical mould filling simulation and casting solidification behaviours. The findings of the numerical research clearly show that the last point of solidification on the die-casted part was the area where shrinkage porosity can be found, the last point on casting to solidify was significantly was the thickest area on the die-casted part and the last point on casting to solidify was the hot spot area of the die-casted part.