Application of Silicon Carbide Chills in Controlling the Solidification Process of Casts Made of IN-713C Nickel Superalloy

The paper presents the method of manufacturing casts made of the IN-713C nickel superalloy using the wax lost investment casting process and silicon carbide chills. The authors designed experimental casts, the gating system and selected the chills material. Wax pattern, ceramic shell mould and experimental casts were prepared for the purposes of research. On the basis of the temperature distribution measurements, the kinetics of the solidification process was determined in the thickened part of the plate cast. This allowed to establish the quantity of phase transitions which occurred during cast cooling process and the approximate values of liquidus, eutectic, solidus and solvus temperatures as well as the solidification time and the average value of cast cooling rate. Non-destructive testing and macroscopic analysis were applied to determine the location and size of shrinkage defects. The authors present the mechanism of solidification and formation of shrinkage defects in casts with and without chills. It was found that the applied chills influence significantly the hot spots and the remaining part of the cast. Their presence allows to create conditions for solidification of IN-713C nickel superalloy cast without shrinkage defects.