|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Characterization of Materials through High Resolution Imaging
||Using the Rotation Vector Base Line Electron Back Scatter Diffraction (RVB-EBSD) Method to Characterize Single Crystal Cast Microstructures
||Pascal Thome, Felicitas Scholz, Jan Frenzel, Gunther Eggeler
|On-Site Speaker (Planned)
We present the Rotation Vector Base Line Electron Back Scatter Diffraction (RVB-EBSD) method, a new correlative orientation imaging method for scanning electron microscopy (OIM/SEM). The RVB-EBSD method was developed to study crystal mosaicity in as-cast Ni-base superalloy single crystals (SX). The technique allows to quantify small crystallographic deviation angles between individual dendrites and to interpret associated accommodation processes in terms of geometrically necessary dislocations (GNDs). The RVB-EBSD method was inspired by previous seminal approaches which use cross correlation EBSD procedures. A rotation vector approximation and a correction procedure, which relies on a base line function, are used. The method moreover features a novel way of intuitive color coding. We show an in-depth analysis of the crystallographic relations which arise from the competitive growth of dendrites. Emphasis is placed on a comparison between SX produced by a conventional Bridgman process and SX produced by selective electron beam melting (SEBM).