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Updated: May 10, 2026

Characterization of Ultra-fine Grained and Nanocrystalline Materials Using Transmission Kikuchi Diffraction
Published on: April 1, 2017
Electron diffraction of ThMn₁₂/Th₂Zn₁₇-type structures in the Nd-Fe-Ti system
Daniela Nunes1, António P Gonçalves, Patricia A Carvalho
1ICEMS, Instituto Superior Técnico, Universidade Técnica de Lisboa, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
Abstract:
Nd:11Fe:Ti alloys prepared by arc melting followed by splat quenching and annealing have been investigated by electron microscopy. The as-cast microstructure evidenced an α-Fe(Ti) --> NdFe₁₁Ti --> Nd₂(Fe,Ti)₁₇ solidification sequence compatible with a cascade of peritectic reactions. The Nd₂(Fe,Ti)₁₇ phase was not detected in the microstructure of the splat-quenched materials, but after annealing the ternary compound grains consisted of a mixture of ThMn₁₂-type and Th₂Zn₁₇-type structures exhibiting a consistent (020)₁:₁₂//(003)₂:₁₇ and [100]₁:₁₂//[110]₂:₁₇, orientation relation, with the invariant plane sitting at (022)₁:₁₂//(333)₂:₁₇. A series of 3D microdiffraction experiments carried out on grains presenting a random distribution of planar defects has been used to map the reciprocal space of the intergrown phases.
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