Deformation-induced pseudo-twinning and a new superstructure in Ni2Mo precipitates contained in a Ni-25Mo-8Cr alloy

doi:10.1016/1359-6454(96)00005-5

Acta Materialia

Volume 44, Issue 9, September 1996, Pages 3575-3583

https://doi.org/10.1016/1359-6454(96)00005-5 Get rights and content

Abstract

Deformation twinning in a two-phase Ni25Mo8Cr (in wt%) alloy containing Ni₂(Mo, Cr) precipitates in a face centered cubic matrix has been studied by transmission electron microscopy. It has been found that the normal twinning variant in the disordered face centered cubic matrix phase which corresponds to the pseudo-twinning mode in the ordered body centered orthorhombic Ni₂Mo phase changes the atomic arrangement (nearest neighbor environment) such that a new superstructure (called the μ phase) with tetragonal symmetry is produced in the twinned regions of the Ni₂Mo precipitates. Experimental electron diffraction evidence obtained across this pseudo-twinned structure has been correlated with the associated crystallography of the phases and a discussion based on these analytical correlations is presented.

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^†: Now at the Department of Mechanical Engineering, The Johns Hopkins University, Baltimore, MD 21218-2686, U.S.A.

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Deformation-induced pseudo-twinning and a new superstructure in Ni2Mo precipitates contained in a Ni-25Mo-8Cr alloy

Abstract

Acta metall.

Prog. Mater. Sci.

Acta metall.

Physica status solidi

Acta metall.

Phil. Mag.

Deformation-induced pseudo-twinning and a new superstructure in Ni₂Mo precipitates contained in a Ni-25Mo-8Cr alloy