Elastic-strain tensor by Rietveld refinement of diffraction measurements

A procedure to obtain all components of the elastic-strain tensor by simultaneous Rietveld refinement of diffraction patterns collected at different specimen orientations is described. The refined lattice parameters yield the hydrostatic strain component. If the lattice constants of the unstrained reference specimen are not known, the deviatoric strain tensor can still be determined. An anisotropic strain component may be refined for cubic and hexagonal crystal structures along with the isotropic. The method is applied to Al/SiC (short whisker) composites and systematic errors are assessed. (C) 1998 American Institute of Physics. [S0021-8979(98)00320-X].