The article contains basic information associated with the impact of the FSW process parameters on the forming of a weld while friction

welding of aluminium casting alloys. Research was conducted using specially made samples containing a rod of casting alloy mounted in

the wrought alloy in the selected area of FSW tool acting. Research has thrown light on the process of joining materials of significantly

dissimilar physical properties, such as casting alloys and wrought alloys. Metallographic testing of a weld area has revealed the big impact

of welding conditions, especially tool rotational speed, on the degree of metal stirring, grain refinement and shape factor of a weld. As the

result of research it has been stated that at the high tool rotational speed, the metals stirring in a weld is significantly greater than in case of

welding at low rotational speeds, however this fails to influence the strength of a weld. Plastic strain occurring while welding causes very

high refinement of particles in the tested area and changing of their shape towards particles being more equiaxial. In the properly selected

welding conditions it is possible to obtain joints of correct and repeatable structure, however in the case of the accumulation of cavities in

the casting alloy the FSW process not always eliminates them.

The main bulk density representation in the molding material is opening material, refractory granular material with a particle size of 0.02

mm. It forms a shell molds and cores, and therefore in addition to activating the surface of the grain is one of the most important features

angularity and particle size of grains. These last two features specify the porosity and therefore the permeability of the mixture, and

thermal dilatation of tension from braking dilation, the thermal conductivity of the mixture and even largely affect the strength of molds

and cores, and thus the surface quality of castings. [1]

Today foundries, which use the cast iron for produce of casts, are struggling with surface defects on the casts. One of these defects are

veining. They can be eliminated in several ways. Veining are foundry defects, which arise as a result of tensions generated at the interface

of the mold and metal. This tension also arises due to abrupt thermal expansion of silica sand and is therefore in the development of

veining on the surface of casts deal primarily influences and characteristics of the filler material – opening material in the production of

iron castings.

The mathematical model and numerical simulations of the solidification of a cylindrical shaped casting, which take into account the process of filling the mould cavity by liquid metal and feeding the casting through the riser during its solidification, are presented in the paper. Mutual dependence of thermal and flow phenomena were taken into account because have an essential influence on solidification process. The effect of the riser shape on the effectiveness of feeding of the solidifying casting was determined. In order to obtain the casting without shrinkage defects, an appropriate selection of riser shape was made, which is important for foundry practice. Numerical calculations of the solidification process of system consisting of the casting and the conical or cylindrical riser were carried out. The velocity fields have been obtained from the solution of momentum equations and continuity equation, while temperature fields from solving the equation of heat conductivity containing the convection term. Changes in thermo-physical parameters as a function of temperature were considered. The finite element method (FEM) was used to solve the problem.

The mathematical model and numerical simulations of the solidification of a cylindrical casting, which take into account the process of the mould cavity filling by liquid metal and the feeding of the casting through the conical riser during its solidification, are proposed in the paper. The interdependence of thermal and flow phenomena were taken into account because they have an essential influence on solidification process. The effect of the pouring temperature and pouring velocity of the metal on the solidification kinetics of the casting was determined. In order to obtain the casting without shrinkage defects, an appropriate selection of these parameters was tried, which is important for foundry practice. The velocity fields have been obtained from the solution of Navier-Stokes equations and continuity equation, while temperature fields from solving the equation of heat conductivity containing the convection term. In the solidification modelling the changes in thermo-physical parameters as a function of temperature were considered. The finite element method (FEM) was used to solve the problem.

The paper indicates the significance of the problem of foundry processes parameters stability supervision and assessment. The parameters, which can be effectively tracked and analysed using dedicated computer systems for data acquisition and exploration (Acquisition and Data Mining systems, A&D systems) were pointed out. The state of research and methods of solving production problems with the help of computational intelligence systems (Computational Intelligence, CI) were characterised. The research part shows capabilities of an original A&DM system in the aspect of selected analyses of recorded data for cast defects (effect) forecast on the example of a chosen iron foundry. Implementation tests and analyses were performed based on selected assortments for grey and nodular cast iron grades (castings with 50 kg maximum weight, casting on automatic moulding lines for disposable green sand moulds). Validation tests results, applied methods and algorithms (the original system’s operation in real production conditions) confirmed the effectiveness of the assumptions and application of the methods described. Usability, as well as benefits of using A&DM systems in foundries are measurable and lead to stabilisation of production conditions in particular sections included in the area of use of these systems, and as a result to improvement of casting quality and reduction of defect number.

The removal of inclusions is a major challenge prior to the casting process, as they cause a discontinuity in the cast material, thereby lowering its mechanical properties and have a negative impact on the feeding capability and fluidity of the liquid alloys. In order to achieve adequate melt quality for casting, it is important to clean the melts from inclusions, for which there are numerous methods that can be used. In the course of the presented research, the inclusion removal efficiency of rotary degassing coupled with the addition of different fluxes was investigated. The effects of various cleaning fluxes on the inclusion content and the susceptibility to pore formation were compared by the investigation of K-mold samples and the evaluation of Density Index values at different stages of melt preparation. The chemical composition of the applied fluxes was characterized by X-ray powder diffraction, while the melting temperature of the fluxes was evaluated by derivatographic measurements. It was found that only the solute hydrogen content of the liquid metal could be significantly reduced during the melt treatments, however, better inclusion removal efficiency could be achieved with fluxes that have a low melting temperature.

The paper includes validation studies of the flow module of the NovaFlow&Solid simulation code. Experiments of ductile iron and gray iron casting in a spiral test of castability were carried out. Casting experiments were then carried out in industrial conditions in the Ferrex Foundry in Poznań and the results are the castability spiral length and local cast iron rate during mould cavity pouring. Simulation tests using NovaFlow&Solid Control Volume code were made. The technological castability test was used to determine thermal-physical data through simplified inversion problem. Influence of physical parameters in the database of simulation code on the spiral length obtained as the result of simulation was analyzed. It was found that critical fraction of capillary flow CLFdown has the biggest impact on cast iron castability in the simulation code. The simulations resulted in defining parameters of gray iron GJL 250 and ductile iron GJS-400-15. For the parameters set, the length of castability spiral in simulations was in accordance with casting experiments.