Stacking faults and crystallite size in mechanically alloyed Cu-Co

Mechanically alloyed Cu-Co (5-90 wt. % Co) has been analyzed using X-ray diffractometry to study microstructural features. All compositions were single phase face-centered cubic. Although some of the observed peak broadening can be attributed to fine grain size and microstrain effects, anomalous hkl-dependent peak broadening and peak shifts are clearly associated with stacking faults. Furthermore, the true grain sizes were > 100 nm, 3-10 times the grain size calculated without considering stacking fault contributions.