Icosahedral Ti–Zr–Ni and hydrogenated Ti–Zr–Ni quasicrystals under high pressure

We present results from the first X-ray diffraction studies under high pressure in icosahedral Ti–Ni–Zr quasicrystals (QCs). The icosahedral Ti53Zr27Ni20 phase and an icosahedral Ti45Zr38Ni17 phase that also contains 0.32 hydrogen atoms for each metal atom were investigated. The icosahedral QC structure is retained up to the highest pressures used. The six-dimensional (6D) lattice parameters were obtained as a function of pressure. The zero-pressure bulk modulus and its pressure derivative were determined for the different samples by fitting the 6D parameter change to a Murnaghan-type equation of state. It is worthwhile mentioning that the hydrogenated sample appears more compressible than the one without hydrogen.