The effect of pressure on the compressibility of aluminum alloys

To obtain reliable data on the properties of liquid metal and create automated control systems, the technological process of molding with crystallization under pressure is studied. A mathematical model of the input and output process parameters is developed. It is established that the compressibility of the melt can represent the main controlled parameter influencing on the physical-mechanical properties of the final products. The obtained castings using this technology are not inferior in their physical and mechanical properties to those produced by forging or stamping.

SUBSTANTIATION OF TECHNOLOGICAL MODES OF PROCESSING CRYSTALLIZING METAL BY PRESSURE USING THE PROCAST SOFTWARE PRODUCT

The possibility of modeling the casting process with crystallization under pressure in the ProCast software package is considered. Simulation results are compared with experimental values. The study of the process is carried out on a horizontal hydraulic press, using technological equipment for the production of cylindrical blanks Ø90× 70 mm. The stages of modeling include a sequence of actions: preparing the geometry of the 3D model of the foundry block; drawing a surface grid using the functions sewn into the program; determination of thermophysical properties and setting boundary conditions. Using solvers, the filling of the mold and the temperature distribution in the mold, taking into account the pouring time, were simulated. In the work, the distribution of macroporosity inside the casting was calculated. Comparing the simulation results and the data obtained experimentally, it is concluded that the ProCast software product is adequate and can be used to solve scientific and applied problems

Simulation of solidification during crystallization under pressure

The paper deals with squeeze casting technology. The influence of process parameters variation (casting temperature, mold temperature, pressure) will be observed. The experimentally obtained boundary conditions (heat flow, HTC) will be verified using the ProCast simulation software. Shape influence on the mold filling process and the temperature field under pressure will be evaluated. To evaluate the mechanical properties, a tensile test was performed. Three identical samples were cast for each parameters change. From these samples the average values of the mechanical properties were measured and calculated. The thickness of the flat test samples was 3.15, 4, 5, 6.3, 8 mm with a sample width of 10 mm. For gravity cast of the casting, the mechanical properties of the thinner parts were higher. At the pressure influenced castings, the mechanical properties were higher in the thicker parts of the casting.

EN AW-2024 Wrought Aluminum Alloy Processed by Casting with Crystallization under Pressure

By using the wrought aluminum alloys can be created castings with higher mechanical properties than the castings made of standard foundry aluminum alloys, but it is necessary to handle the process of making sound castings without any defects such as hot tears and shrinkage porosity. In experiments, we have been studied of wrought aluminum alloy EN AW-2024 which has been processed by the casting with crystallization under pressure with forced flow. Castings were heat treated by standard T6 heat treatment.

Effect of Technological Parameters on the AlSi12 Alloy Microstructure During Crystallization Under Pressure

The paper deals with the impact of technological parameters on the heat transfer coefficient and microstructure in AlSi12 alloy using squeeze casting technology. The casting with crystallization under pressure was used, specifically direct squeeze casting method. The goal was to affect crystallization by pressure with a value 100 and 150 MPa. The pressure applied to the melt causes a significant increase of the coefficient of heat transfer between the melt and the mold. There is an increase in heat flow by approximately 50% and the heat transfer coefficient of up to 100-fold, depending on the casting conditions. The change in cooling rate influences the morphology of the silicon particles and intermetallic phases. A change of excluded needles to a rod-shaped geometry with significantly shorter length occurs when used gravity casting method. By using the pressure of 150 MPa during the crystallization process, in the structure can be observed an irregular silica particles, but the size does not exceed 25 microns.