Simulation of Centrifugal Casting and Structure of Fe-Ni-Co Super-Invar Alloy

Abstract

This paper is focused on multi-scale modeling of solidification and alloy microstructure evolution through computer-aided simulation of the technological processes. Microstructure characterization of cast alloy after centrifugal casting including grain size, dendrite cell size and porosity is of interest in this paper. The centrifugal technological process was simulated using special LVMFlow program for computer-aided analysis of casting technologies to predict shrinkage porosity in axi-symmetric part blanks. The cast blanks were made of Fe-Ni-Co alloy with low thermal expansion and after turning could be used as bearing parts in contact with glass or ceramics. A method of combined simulation of technological processes and operating regimes of cast components was developed. The proposed method of simulating the complicated model allows separating the component from casting geometry in CAE postprocessor and the plot distribution of calculated parameters over the component. Also, this method allows varying diameters of hollow cylindrical casting and choosing the best location of components relative to the predicted porosity in the blank for high quality turning. The distribution of temperature and porosity could be used for more precise calculation of internal stresses in cast component under loading conditions with respect to the structural factors. The structural parameter was stated on a base of the calculated temperature fields to associate grain structure of cast alloy with solidification conditions. The austenitic microstructure of Fe-Ni-Co super-invar alloy was studied on the samples, which were cut from the axi-symmetric part after turning the blank. The calculated structural parameter was assigned with the types of grain structure.