High-Pressure X-Ray Diffraction Experiments on Icosahedral Ti-Zr-Ni - Evidence for a Low Shear Modulus and a High Poisson's Ratio

摘要

In situ high-pressure X-ray diffraction experiments have been performed on quasicrystalline Ti-Zr-Ni in energy dispersive mode using synchrotron radiation. Pressures up to 30 GPa were generated using a diamond anvil cell. When plotting the hypercubic lattice parameter versus pressure an additional expansive strain could be observed which is caused by non-hydrostatic stress. Using the model of Singh and Kennedy the shear modulus of Ti-Zr-Ni could be stimated to be #mu# approx = 7 GPa, Poisson's ratio was calculated to v = 0.48 +- 0.015.