Abstract
Single crystals of nickel having a long length were prepared and their thermal expansions and Young’s moduli were measured over the temperature range 0° to 500°C by a dilatometer and by means of a vibrator-controlled oscillator system. From the measured values, the elastic parameters Sij, Young’s modulus for three principal orientations of the single crystals and for a polycrystal of nickel were calculated. It has been known that the temperature changes of the Young’s modulus for the three principal orientations and a polycrystal of nickel are similar to each other, and the calculated values of the Young’s modulus for a polycrystal agrees well with the measured values of the annealed polycrystal specimen. The calculated Young’s moduli at 20°C are 1.21, 2.04, 2.62 and 1.90×1012 dyn/cm2, respectively, for the ⟨100⟩, ⟨110⟩, ⟨111⟩ orientations of the single crystals and for the polycrystal. The crystal anisotropy E⟨111⟩⁄E⟨100⟩ of the nickel single crystal at 20°C and 150°C are 2.17 and 2.49, respectively.
