The Unidirectional Crystallization of Metals and Alloys (Turbine Blades)

Abstract In the work, ceramics (zirconium silicate, aluminosilicates, mullite, zirconium dioxide), waxes, and binders used in investment casting of nickel-based superalloys have been characterized. Additionally, methodology of wax model pattern and ceramic molds for investment casting process have been discussed. The manufacturing methods (Bridgman, liquid metal cooling (LMC), gas cooling casting (GCC)) of single crystal and directionally solidified (DS) castings (mainly of aircraft engine and gas turbine blades) from nickel-based superalloys were presented. Moreover, the geometry of starter and selector in single crystal (SC) castings has been characterized. In the work, chemical composition of nickel-based superalloys (DS and SC), heat treatment technology, and test methods (macro-and microstructure, mechanical properties, crystalline perfection by Laue method, EBSD, and diffractometry) of nickel-based superalloys casting were shown and the principles of modeling the process of directional solidification (nucleation and grain growth) by finite element method (FEM) method has been described.