- The elastic constants of high quality single crystals of Cr3Si (cubic A15 crystal structure) grown in an optical floating zone furnace were measured by ultrasonic methods and compared to the indentation modulus determined by nanoindentation techniques. The measured indentation moduli are within 5% of the Vlassak-Nix predictions for elastically anisotropic materials provided a correction is made for the triangular cross-section of the Berkovich indenter. The indentation moduli of individual lamellae in a directionally solidified Cr-Cr3Si lamellar eutectic composite were also measured to examine how well the procedures apply to small microstructural features. 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.