Crystal structure and lattice dynamics of hydrogen-loaded austenitic steel

We investigated the crystal structure and hydrogen vibrations in a hydrogen-loaded AISI 310 type austenitic steel (Fe-25Cr-20Ni) by neutron diffraction and inelastic neutron scattering. The samples with hydrogen content ofH/Me = 0.43 and 0.92 were prepared in a hydrogen gas atmosphere at pressures up to 7.0 GPa. This doping procedure yields a more homogeneous hydrogen distribution within the sample than cathodic charging and allows clarifying the role of the concentration gradients and stresses on the phase transformation. Only fcc phase with increased lattice parameter was observed in both samples, however frequency spectra show a modification of the broad peak into two components at higher H content