Investment casting of gas turbine blade by used of rapid technologies

This study has investigated the ability of two different rapid technologies, namely, MultiJet Modeling (MJM) and silicone rubber molding to manufacture investment casting pattern of gas turbine blade. For this reason, the second stage blade of Ruston TA 1750 (1.3MW) gas turbine was digitized using CMM and then its wax pattern manufactured by MJM technology and silicone rubber molding technique. Regarding the inspection results of manufactured patterns, maximum deviation of MJM pattern was -0.111mm. While for pattern fabricated using silicone rubber molding, maximum deviation was +0.298 mm. Considering results of this experimental research, both techniques are usable to manufacture expendable pattern of gas turbine blade but in terms of part accuracy, silicone rubber molding is not successful approach for manufacturing of blade expendable patterns. MJM technology enjoys more dimensional accuracy as well as more ability compare with silicone rubber molding technique