Die casting is a production process, which enables production of castings with complex geometry and due to many advantages, it is widely used in automobile industry with high quality standards. The aim of my master´s thesis was the improvement of final quality of casting of production project in which we noticed a problem of shrinkage porosity in the main part of casting. We implemented local squeeze casting on a critical area in a traditional die casting technology. The implementation was based on detail numerical calculation of casting process and already existing experiences with die casting. We performed tests on die casting machine with ten different delay times for activation of local squeezing from the time, when the casting cavity was full. In total, we poured 200 samples. During our test we used lower pressure than it is usually used in serial production. The quality of samples was analyzed with four different methods (RTG, CT analysis, metalography and analysies of depths of core squeezing). We didn't found critical shrinkage porosity with none of them. We found out that different delay times influent on the depths of core squeezing, but without any special impact on final quality of casting. The lower pressure, used during the process, didn't influence on the quality of casting, but it less burdened the die casting machine and consequently prolong its shelf life. Our goal was achieved above the expectations and it greatly contributed to the economic efficiency of the production process.
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