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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.

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.

The paper presents the results of the heat transfer area during the cooling process of steel test die with water mist which consist the flow of air in the range 150÷350 l/min and 0.05 0.24 l/min of water. Temperature change in the thickness of die by means showing with the thermal curves and the temperature gradient and temperature distribution in the space between the nozzle and the cooled surface of the metal mold using a thermal imaging camera and thermocouples measurement. The course of changes in the temperature gradient and the received heat flux from the die while cooling its with the flow of air and water mist stream. It has been shown that the use of water mist with a variable flow of air and water controls the process of heat transfer process between the permanent molds, and a stream of water mist.

The paper presents the results of crystallization and cooling process of silumin AlSi9 and temperature distribution in the wall of research casting dies made of cast iron and steel in the temperature range 650100C during casting of silumin using water mist cooling consisting with air compressed (0,30,4 MPa) and water (0,350,45 MPa). It’s shown the nature and rate of change of casting die temperature and the formation of the temperature gradient at the wall thickness in the axis of the nozzle cooling the outer surface of the wall of casting die. Using derivative curves and regression models were compared to the temporary and average speed of crystallization and cooling of the casting in the 75÷200C temperature range. The differences of microstructure resulting from a change in the type of casting die, wall thickness of casting and the use of cooling water mist. It has been shown that the use of water mist and the changing wall thickness of die and the casting cooled pointwise lets you control the crystallization process, microstructure and quality of the silumin casting.

The paper presents the results of the process of crystallization and cooling of the AlSi11 silumin and temperature distribution in the wall of iron and bronze research casting die in the temperature field of 750 to 100°C in casting of the silumin with use of water cooling mist in the air at a pressure of 0.30 to 0.40MPa and the water from 0.35 to 0.45MPa. Showing the nature and rate of change of temperature in die casting and the formation of temperature gradient on the thickness of the die casting wall in the direction of the nozzle surface of the outer wall of the cooling die casting. Using derivation curves and regression equations there has been compared: the mean and instantaneous rates of crystallization and cooling cast in values of 750 ÷ 200°C. In addition, there are presented the differences arising from the microstructure change of the die’s type and thickness of its walls, the thickness of cast and the fact of using cooling water mist. The conduct of the changes of the hardness of the cast as a result of the applied cooling method of the die casting. It has been shown that the use of water mist with a variability of the die’s wall thickness in the cooling zone gives control of the crystallization process, microstructure and mechanical properties of the final silumin cast.

This project is showing investigation results of cooling process of casting die in the temperature range 570÷100 °C with 0.40 MPa compressed air and water mist streamed under pressure 0.25÷0.45 MPa in air jet 0.25÷0.50 MPa using open cooling system.The character and the speed of changes of temperature, forming of the temperture’s gradient along parallel layer to cooled surface of die is shawing with thermal and derivative curves. The effect of kind of cooling factor on the temperature and time and distance from cooling nozzle is presented in the paper. A designed device for generating the water mist cooling the die and the view of sprying water stream is shown here. It’s proved that using of the water mist together with the change of heat transfer interface increases intensity of cooling in the zone and makes less the range cooling zone and reduces the porosity of cast microstructure.

This project is showing investigation results of heat transfer process between cast iron die and environment during cooling of die in the temperature range 600÷100 C with compressed air, spray water and water mist streamed under pressure 0.35 0.45 MPa in air jet0.3 0.4 MPa .At the paper are shown results of cooling die’s flat wall using open cooling system. The temperature gradient was presented at die’s wallthickness and calculated thermal curve for cooling surface. The calculation results of heat transfer coefficient α were presented between die and researched cooling factors and also mathematical models of α coefficient depending on surface temperature. Revealed that coefficient α has the biggest value’s range for die cooling with water mist under pressure 0.3/0.35 MPa.

At work research findings of the process of cooling the research casting die in the range of the 600-100°C temperature were presented and of the research-production casting die while pouring the cycle out cooled with compressed air about the pressure 0.6 MPa and the water mist about the pressure of air and water appropriately 0.3/0.35 MPa. The character and the speed of the temperature changes in the die and being formed of gradient of the temperature on the thickness partition walls were shown the die with the help of thermal and derivative curves. A course of changes was presented to the density of the thermal stream during cooling and in function of the temperature as well as results were shown a computer simulation of the process of pouring the production casting die. A scheme of the device for generating the water mist cooling the die and an image of spraying water were shown with the help of the designed rotary sprayer. They showed that applying the water mist for cooling dies is increasing the intensity of casting process and is accelerating it.