Crystallographic Orientation Influence on the Serrated Yielding Behavior of a Single-Crystal Superalloy

Since Ni-based single-crystal superalloys are anisotropic materials, their behavior in different crystal orientations is of great interest. In this study, the yielding behavior in both tension and compression for [Formula: see text] , [Formula: see text] and [Formula: see text] oriented materials at 500 °C has been investigated. The [Formula: see text] direction showed a serrated yielding behavior, a great tension/compression asymmetry in yield strength and visible deformation bands. However, the [Formula: see text] and [Formula: see text] directions showed a more homogeneous yielding, less tension/compression asymmetry in yield strength and no deformation bands. Microstructure investigations showed that the serrated yielding behavior of the [Formula: see text] direction can be attributed to the appearance of dynamic strain aging (DSA) and that only one slip system is active in this direction during plastic deformation.