The influence of the chill on the AlSi7Mg alloy properties after the heat treatment T6, was realised in the system of the horizontally cast plate of dimensions 160x240 mm and thickness of 10 and 15 m. The cooling course in individual casting zones was recorded, which allowed to determine the solidification rate. Castings were subjected to the heat treatment T6 process. Several properties of the alloy such as: hardness BHN, density, tensile strength UTS, elongation %E were determined. The microstructure images were presented and the structural SDAS parameter determined. The performed investigations as well as the analysis of the results allowed to determine the influence zone of the chill. The research shows that there is a certain dependence between the thickness of the casting wall and the influence zone of the chill, being not less than 2g, where g is the casting wall thickness. The next aim of successive investigations will be finding the confirmation that there is the dependence between the casting wall thickness and the influence zone of the chill for other thicknesses of walls. We would like to prove that this principle is of a universal character.

This article presents an evaluation of the quality of the connection between the ZrO2-Y2O3 coating with the NiAl interlayer and AlSi7Mg alloy casting, utilising the scratch test method. The study analysed the ZrO2-Y2O3 coating with the NiAl interlayer applied using the APS (Atmospheric Plasma Spraying) method. The chemical composition of the zirconia coating and the interlayer was analysed. The core element of the study involves scratch test examinations of the analysed coatings, determining their scratch resistance. Scanning electron microscopy was used to analyse the scratch area to identify any potential cracks or delaminations at the casting-NiAl interlayer boundary, and the NiAl interlayer-ZrO2-Y2O3 coating boundary. Based on the conducted studies, high-quality connection of the ZrO2-Y2O3 coating with the NiAl interlayer and the AlSi7Mg alloy casting was concluded. The results of these studies will form the basis for further work on the application of TBC (Thermal Barrier Coating) to improve the operational durability of aluminium alloy parts working under high-temperature conditions.