Download citation
Download citation
link to html
The space group of a new metastable orthorhombic Al2Cu phase, located in the Al-rich interfacial region of an Al–Cu friction stir weld, was unambiguously identified as Ic2m by a recently developed systematic method combining precession electron diffraction and convergent-beam electron diffraction. This metastable phase has the same tetragonal lattice as its stable θ-Al2Cu counterpart (tetragonal, I4/mcm, No. 140). The tetragonal-to-ortho­rhombic symmetry lowering is due to slight modifications of the atomic positions in the unit cell. This metastable phase can be transformed into the stable θ-Al2Cu phase by in situ irradiation within the transmission electron microscope.

Follow J. Appl. Cryst.
Sign up for e-alerts
Follow J. Appl. Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds