Properties of made by different methods of RP impeller foundry patterns

This article presents the tests of properties of foundry patterns of turbocharger turbine impeller. Impellers prototypes were predestinated for casting by method losing patterns. There were carried out tests of these prototypes made by different methods of Rapid Prototyping (RP). Two impeller were made by growth methods: stereolitography (SLA) and three dimensional printing (3DP). One prototype was made by the method of Vacuum Casting as a wax casting. Tests were executed in the Department of Machine Design of Rzeszow University of Technology in cooperation with WSK PZL Rzeszow and Car Technology Krakow. First impeller was carried out by method of stereolitography on SLA 250 plant. That pattern was also used to carry out silicon matrix for casting of wax pattern. Next pattern was printed by three dimensional printer Z510 from the powder ZP14. Good removability of the pattern from the mould is particularly essential for impellers of small turbines with blades of small thickness of their section. All pattern were tested on their removability from the ceramic mould. The best melting properties had the wax pattern. Patterns made from resin SL5170 (SLA) and powder ZP14 (3DP) were removed in the process of burning but about 1% of soot was left in the mould.