BSTRACTOrdered B2 precipitates typically nucleate at the grains-boundaries of

fcc

-based high entropy alloys. Here

we report a novel mixed-mode coupled displacive-diffusional transformation resulting in homogeneously distributed intra-granular B2 precipitates within the

fcc

matrix. Severe plastic deformation forms compositionally invariant

metastable distorted

fcc

structures

resembling hexagon-like templates

at the deformation twin-boundaries. These shear-induced hexagon-like templates correspond to the symmetry of the {111}

bcc

planes

and act as sites for B2 nucleation

establishing the

fcc-bcc

Kurdjumov–Sachs (KS) orientation relationship. However

the composition of these B2 precipitates is far-from-equilibrium. Subsequent isothermal annealing causes solute partitioning driving the composition of the B2 precipitates towards equilibrium.