The influence of mechanical activation of ceramic powders on the quality of casting coatings

Abstract

In order to increase the efficiency of coatings, the influence of mechanical activation has been studied by monitoring the changes of surface and energy state, the change of structure and properties of ceramic powders under the influence of mechanical forces at dispersion. Thus prepared ceramic powders were utilized as a filler in synthesis of ceramic coatings for sand molds and for application in the EPC casting process. The aim was to monitor the changes in quality of ceramic powders after mechanical activation and their influence on the properties of coatings and, respectively, on the properties of the castings obtained. A dried layer of ceramic coating, which may vary in thickness, applied on either a sand mold or an evaporable polymeric pattern (EPC casting process) is used as an efficient barrier for liquid metal during the inflow stage. The tests showed a positive influence of the process of mechanical activation of ceramic fillers on the coating properties, as well as on improvement of surface quality of the castings obtained. .

U cilju povećanja efikasnosti premaza izučavan je i uticaj mehaničke aktivacije keramičkih prahova kroz praćenje promene površine i energetskog stanja, promene strukture i svojstava keramičkih prahova pod dejstvom mehaničkih sila pri dispergovanju. Ovako pripremljeni keramički prahovi korišćeni su kao punilac u sintezi keramičkih premaza za peščane kalupe i za primenu u EPC procesu livenja. Cilj je bio praćenje promena kvaliteta keramičkih prahova nakon mehaničke aktivacije i njihov uticaj na svojstva premaza, odnosno svojstva dobijenih odlivaka. Osušeni sloj keramičkog premaza, koji može da bude različite debljine, nanesen na peščani kalup ili isparljiv polimerni model (EPC proces livenja) služi kao efikasna barijera tečnom metalu u fazi ulivanja. Istraživanja su pokazala pozitivan uticaj procesa mehaničke aktivacije keramičkih punila na svojstva premaza i na poboljšanje kvaliteta površine dobijenih odlivaka. prahova, EPC proces livenja, kvalitet odlivaka. .