Tool for automatic macrozone characterization from EBSD data sets of titanium alloys

B. Fernández Silva*, M. Jackson, K. Fox, B. P. Wynne

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)
47 Downloads (Pure)

Abstract

Microtexture heterogeneities are commonly found in titanium forgings because of the thermomechanical processing. Also known as macrozones, these regions can reach millimetres in length, with grains sharing a similar crystallographic orientation leading to less resistance to crack propagation. Since the link between macrozones and the reduction of cold‐dwell‐fatigue performance on rotative components in gas turbine engines was established, efforts have been put into macrozone definition and characterization. The electron backscatter diffraction (EBSD) technique, widely used for texture analysis, allows for a qualitative macrozone characterization; however, further processing is required to define the boundaries and disorientation spread of each macrozone. Current approaches often use c‐axis misorientation criteria, but this can sometimes lead to a large disorientation spread within a macrozone. This article describes the development and application of a computational tool implemented in MATLAB for automatic macrozone identification from EBSD data sets on the basis of a more conservative approach where both the c‐axis tilting and rotation are considered. The tool allows for detection of macrozones according to the disorientation angle and density‐fraction criteria. The clustering efficiency is validated by pole‐figure plots, and the effects of the key parameters defining the macrozone clustering (disorientation and fraction) are discussed. In addition, this tool was successfully applied to both fully equiaxed and bimodal microstructures of titanium forgings.
Original languageEnglish
Pages (from-to)737-749
Number of pages13
JournalJournal of Applied Crystallography
Volume56
Issue numberPt 3
Early online date23 May 2023
DOIs
Publication statusPublished - 1 Jun 2023

Keywords

  • characterization
  • titanium alloys
  • crystal misorientation criteria
  • macrozones
  • texture
  • electron backscatter diffraction

Fingerprint

Dive into the research topics of 'Tool for automatic macrozone characterization from EBSD data sets of titanium alloys'. Together they form a unique fingerprint.

Cite this