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The work is a continuation of research concerning the influence of intensive cooling of permanent mold in order to increase the casting efficiency of aluminium alloys using the multipoint water mist cooling system. The paper presents results of investigation of crystallization process and microstructure of multicomponent synthetic hypereutectic alloy AlSi20CuNiCoMg. The study was conducted for unmodified silumin on the research station allowing the cooling of the special permanent sampler using a program of computer control. Furthermore, the study used a thermal imaging camera to analyze the solidification process of multicomponent alloy. The study demonstrated that the use of mold cooled with water mist stream allows in wide range to form the microstructure of hypereutectic multicomponent silumin. It leads to higher homogeneity of microstructure and refinement of crystallizing phases of casting.

Unmodified AlSi20 alloy were casted at the research station, allowing for sequential multipoint cooling using a dedicated computer- controlled program. This method allows for the formation of the microstructure of hypereutectic AlSi20 alloy and also increases hardness. Primary silicon dendrites were found in the microstructure of cooled samples. Based on these dendrites, the formation of primary silicon particles is explained. Cooling of casting die with a water mist stream causes changes in solidification, which leads to expansion of the boundary layer with columnar crystals and shrinkage of the core zone with equiaxed crystals. It also causes more regular hardness distribution around pre-eutectic Si crystals, which can lead to tensile strength and machinability improvement.

The work is a continuation of research on the use water mist cooling in order to increase efficiency of die-casting aluminum alloys using multipoint water mist cooling system. The paper presents results of investigation of crystallization process and microstructure of synthetic hypereutectic AlSi20 alloy. Casts were made in permanent mold cooled with water mist stream. The study was conducted for unmodified AlSi20 alloy and modified with phosphorus, titanium and boron on the research station allowing sequential multipoint cooling using a dedicated program of computer control. The study demonstrated that the use of mold cooled with water mist stream allows the formation of the microstructure of hypereutectic silumins. A wide range of solidification temperature of hypereutectic silumins increases the potential impact of changes in the cooling rate on a size, a number and a morphology of preeutectic silicon and eutectic α+β (Al+Si).

The work is a continuation of research on the use of water mist cooling in order to increase efficiency of the die-casting process for aluminum alloys. The paper describes the multipoint sequential cooling system of the casting die and its computer control and monitoring. It also includes results of the tests and analysis of cooling methods during making of the casting. These methods differ from each other in the sequence of casting die cooling and cause effective changes in microstructure and mechanical properties of castings made of AlSi11 alloy. The study demonstrated that the use of multipoint sequential cooling with water mist affects the microstructure refinement and reduces the segregation in the cast as well as more than by 20% increases the mechanical properties of castings in the rough state. The study also demonstrates that the sequential cooling of casting die accelerates the cooling of the casting and shortens die-casting cycle.

Structure of Water Mist Stream and its Impact on Cooling Efficiency of Casting Die The work is a continuation of research on the use water mist cooling in order to increase efficiency of die-casting aluminum alloys. The paper presents results of research and analysis process, spraying water and generated a stream of water mist, the effect of the type of nozzle, the nozzle size and shape of the emitting of the water mist on the wall surface of casting die on the microstructure and geometry of water mist stream and cooling efficiency. Tests were used to perform high-speed camera to record video in the visible and infrared camera. Results were used to develop a computerized image analysis and statistical analysis. The study showed that there are statistical relationships between water and air flow and geometry of the nozzle and nozzle emitting a stream of microstructure parameters of water mist and heat the incoming stream. These relationships are described mathematical models that allow you to control the generating of adequate stream of water mist and a further consequence, the cooling efficiency of casting die.