The purpose of this thesis is to manufacture casted plates, with required geometrical shape and chemical composition from copper alloys using the process of gravity sand casting. We decided that the method of making sand mixture with water glass (CO2 metod) is the most appropriate in our case, because of its simplicity and efficiency of making a small number of products. Sand mixture was made with water glass and hardened by blowing carbon dioxide through the mould We designed a runner system and formed patterns from wood. With three different copper alloys; CuSn6Zn3Pb2, CuSn10 and CuZn7Sn7Pb5 we had to manufacture a number of plates of three different sizes. These alloys were prepared in an electric resistance furnace with charge materials; secondary material (PbSn8) and technically pure Sn, Pb and Zn. We calculated mass balance and then compared theoretical results with actual results that we got from measuring chemical composition of the castings. By doing this, we calculated the yield of each individual element; for lead is 72,02 %, for zinc 78,02 %, for tin 90,37% and for copper 98,86 %. Manufactured castings matched required geometrical shape and chemical composition.
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