Strength and texture of Pt compressed to 63 GPa

Angle-and energy-dispersive X-ray diffraction experiments in a radial geometry were performed in the diamond anvil cell on polycrystalline platinum samples at pressures up to 63 GPa. Observed yield strength and texture depend on grain size. For samples with 70-300-nm particle size, the yield strength is 5-6 GPa at similar to 60 GPa. Coarse-grained (similar to 2-mu m particles) Pt has a much lower yield strength of 1-1.5 GPa at similar to 60 GPa. Face-centered cubic metals Pt and Au have lower strength to shear modulus ratio than body-centered cubic or hexagonal close-packed metals. While a 300-nm particle sample exhibits the texture expected of face-centered-cubic metals under compression, smaller and larger particles show a weak mixed and texture under compression. Differences in texture development may also occur due to deviations from uniaxial stress under compression in the diamond anvil cell. (C) 2015 AIP Publishing LLC