Mode of boron solubility in ferrous alloys

X-ray and neutron diffractometry and inelastic neutron scattering studies o n a set of cast ferritic iron-chromium alloys containing boron indicate tha t the dissolved boron is present interstitially rather than substitutionall y within the alpha -Fe,Cr matrix. Inelastic neutron scattering spectra of t he alloys may be interpreted in terms of the phonon dispersion curves for a lpha -Fe. These spectra show small shifts in the frequencies of particular phonons, indicative of lattice disruption by the presence of interstitial a toms. These results were subsequently confirmed by internal friction measur ements.