Analysis of Shrinkage & Warpage in Ceramic Injection Molding of HPT Vane Leading Edge Core of a Gas Turbine Casting (original) (raw)

Analysis of Shrinkage & Warpage in Ceramic Injection Molding of HPT Vane Leading Edge Core of a Gas Turbine Casting

Gas Turbines in Aerospace applications operate at extreme conditions of temperatures and stresses. The Blade/Vane components of these turbines have sculpted, twisted and hollow aerofoil geometry made using Nickel based super alloys through the investment casting process. Hollow wax patterns produced with use of ceramic cores are the first input to the investment casting process. The quantification and prediction of dimensional deviations due to shrinkage & warpage, which are dependent on injection parameters, shape of part and gating system adopted, is mandatory to arrive at acceptable tooling and castings. The insight of flow pattern in the die cavity imparts knowledge of possible weld lines, air-trap, jetting etc. The gating system may be designed, based on simulation results, to minimise such defect. The effects of injection molding parameters such as holding time, packing pressure and melt temperature on shrinkage and warpage of green part using moldex3D software are studied in this paper.