Determination of Stacking Fault Probabilities and Internal Strains from Lattice Parameter and Line Profile Measurements of Cold Worked A-Cu-Zn and A-Cu-SN Filings

摘要

Copper-zinc and copper-tin terminal solutions were cold worked by making filings at room temperature. The plots of the lattice parameter calculated from the peak position of the individual reflections as a function of costheta cottheta proved to be linear for all annealed powder samples. The large scatter of the individual a sub hkl values of the cold worked filings could be related to the occurrence of deformation stacking faults, segregation and internal stresses, and the true lattice parameters. The lattice parameter of the Cu-Zn alloys is larger whereas that of the Cu-Sn alloys is smaller than the corresponding values. The deformation fault probability a increases with increasing solute concentration. The combined twin fault probabilities and extrinsic fault probability were determined from the displacements of the center of gravity from the peak maximum positions of the (111) and (200) reflections.