Utilisation of nanoparticles in technologies of producing castings for the needs of power engineering

Abstract

Castings constitute important installation elements in the traditional coal, gaseous or nuclear power plants. Cast elements are also used in installations of the so-called renewable energy. Utilising nanoparticles in the foundry industry leads to improvements in the quality of produced castings and thus to the cost production lowering. Better properties of moulds and cores were achieved as a result of utilisation of nanoparticles in sand technologies. Works carried out in the Faculty of Foundry Engineering, AGH-UST, concerned the water-glass binder modification by nanoparticles of metal oxides (zinc oxide and magnesium oxide) in alcoholic solvents (methanol, ethanol and propanol). Nanoparticles were synthesised in the electrochemical process by anodic dissolution of metals as well as by the thermal method. The nanoparticles of zinc oxide obtained in the electrochemical process are of the structure of equiaxial agglomerates of various sizes depending on the applied alcohol. The largest nanoparticles were obtained from the methyl alcohol solution (~50 nm), while the smallest (≤20 nm) from the propyl alcohol solution. The highest tensile strength (above 25% larger than the strength of the moulding sand with no modified water-glass) was obtained by the moulding sand in which water-glass was the binder modified by the colloidal solution of zinc oxide nanoparticles in propyl alcohol.