Surface precursor effects above the martensitic transition inV3Si andNb3Sn

Abstract

High-resolution x-ray and neutron scattering studies of the martensitic phase transition in ${\mathrm{V}}_3$Si and ${\mathrm{Nb}}_3$Sn show precursory broadening of the Bragg peaks as the transition is approached from above. No broadening is observed in nontransforming ${\mathrm{V}}_3$Si. After etching there is a drastic reduction of the peak broadening. At the same time the statistical domain population in the tetragonal phase prior to etching becomes single domain.