Aluminium alloys are, due to their properties, an important part of all shaped castings made especially for the aerospace and automotive industry. One of the widely used alloys, for the production of castings in the automotive industry, is the AlSi7Mg0.3 alloy. In the experiment, which is the content of this paper, two castings from AlSi7Mg0.3 alloy were tested. Iron is a common contaminant in aluminium alloys and its content in the alloy is increased by the use of secondary aluminium alloys or by various causes during the production process itself. In the experiment, the corrosion resistance of castings was evaluated (in one of them the increased Fe content) under the specified conditions in the corrosion chamber with salt mist. Corrosion properties were evaluated using confocal laser microscopy. Based on the results of the microscopic analysis, the relevant conclusions were formulated. From the experiment, it is evident that the increased iron content (0.319 [wt. %]) does not, in this case, affect the corrosion resistance of casting.

The usage of aluminium alloys has an increasing trend in the manufacturing industry in recent years. This fact is connected with their ability to combine their very good properties. Characteristics of aluminium are low specific weight, very good thermal and electrical conductivity, and ductility. However, the major disadvantages are low strength and hardness. Therefore the aluminium alloys are alloyed with the elements, which would significantly improve the properties of aluminium. The machining process of aluminium alloys is influenced by many factors that affect the machinability. These factors are for example process conditions, cutting tool material, cutting tool geometry, cutting environment or the chemical composition of the machined material itself and microstructure of the workpiece. Due to the different structures, the machinability of aluminium alloys and pure aluminium is significantly different. Factors such as chemical composition, precipitates, the number and position of soft particles or the strain hardening degree affect the behaviour between the cutting tool and the workpiece during machining. When machining the aluminium alloys, there are some problems such as the surface quality, micro-geometry, tool wear, the chip shape, built-up edge formation, etc. The article deals with the surface defect investigation after the machining process, when on the surface of the material stay the visible "snowflakes" after the turning operation. These "snowflakes" were documented and were performed analysis and observation to find the cause of these flakes.

The article deals with geopolymer binder system for core production, especially by dehydration technology and comparison with PUR cold box amin technology. A sodium-potassium type of geopolymer binder is the subject of the research. The goal of the article is the core production and observing of technological properties, storing cores, usage of refractory coating evaluating of properties during the pouring and decoring of casting. The main target of the experiment is casting quality. It was stated that the final surfaces are much more better than PUR cold box amin technology and the internal casting quality is the same, it means without inadmissible internal defects. Worse decoring times were observed. It has been confirmed, that neither emissions, fumes nor unpleasant odours are generated during the production procedure nor during pouring.

Aluminum alloys are often contaminated with non-metallic inclusions. A large number of these phases accelerate the tendency of porosity in castings, significantly reduce corrosion resistance and above all affect mechanical properties. Melting is one of the conventional methods for removing inclusions from melt. The efficiency of this process is influenced by several parameters such as the chemical composition of the melt, the amount of refining substances (wire, salts, tablets), the melting point and the casting method. Therefore, an experiment was performed to evaluate the effect of PROBAT FLUSS MIKRO 100 on the structural integrity in AlSi10Mg alloy. Porosity evaluation was performed by light microscopy. To confirm the results and their reflexes into the practical production of castings, a static tensile test was performed on the cast samples directly in the foundry operation.

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