An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Predicting the Location of Low-Angle Boundaries in Single-Crystal Castings
Published
Author(s)
R E. Napolitano, Robert J. Schaefer
Abstract
A set of nickel-based superalloy single-crystal investment castings was produced and evaluated for crystal perfection. Defect structures near the seed emergence point and other geometric features were examined using x-ray topography. Topographic images were compared with metallographically observed dendritic structures to establish a convergence-fault criterion for the location of low-angle boundaries. A trip-growth model for simulation of the growth of the dentritic network was developed. This model predicts the local primary growth direction and identifies regions of convergent growth. A connectivity parameter is used to map the locations which are most vulnerable to convergence-fault formation. Predictions are compared with experimental observation.
Napolitano, R.
and Schaefer, R.
(2008),
Predicting the Location of Low-Angle Boundaries in Single-Crystal Castings, Journal of Materials Science
(Accessed December 8, 2023)