The rolling textures and microstructures developed in fine grained (2–5 μm diam.)
70:30 brass are different to those found in coarser grained material. The
{111}〈uvw〉γ fibre usually found at medium reductions is not developed but the
normal {110}〈112〉 texture still emerges at higher reductions. The microstructures
are related to these changes. Although twinning is a deformation mode at low
reductions the volume of twins is never large and the twin alignment characteristic of
normal brass at ∼70% reduction does not occur. The pattern of shear band
development is changed and large areas of the microstructure are featureless at high
reductions. Hardness values show an unexpected rise between 60 and 90% reduction
and this is attributed to a Stage IV regime of strain hardening. After annealing at 300
and 900℃ the textures are typical of those found in coarser grained material.
