AbstractA refined x-ray line profile analysis was used to determine the lattice strain distribution and crystallite domain size in nickel and a series of alloys, Ni-Cr, Ni-ThO2 and Ni-Cr-ThO2 in a wide range of thermo-mechanical conditions. Corrections were made for instrumental broadening and doublet broadening according to Stokes and Rachinger respectively, for errors due to the “hook effect”, for terminal errors in the series arising from Instability of the components, and for the presence of stacking faults and twins on the basis of peak shift and asymmetry. The internal consistency of the x-ray data was reviewed critically and good agreement was found. The values of lattice strain and domain size were used to evaluate the presence of a dislocation substructure and the degree of polygonization of the subgraln boundaries.It was concluded that the thoria-free materials developed much higher lattice strains during cold rolling than did the Ni-ThO2, due it is thought to the operation of multiple slip in the latter. The Ni-Cr-ThO2 also developed high lattice strains during cold rolling, similar to those of the thoria-free lattices, and this was explained by the influence of chromium on cross-slip. It was postulated that the regions of high lattice strain act as driving forces in the process of recrystallization and promote grain growth during heat treatment following cold rolling.The x-ray results were correlated with transmission electron microscopy and tensile data in a parallel study in which models for room temperature and high temperature strengthening were proposed.
Estimation of lattice strain in alumina–zirconia nanocomposites by X-ray diffraction peak profile analysis