Nanocrystalline gold (n-Au) specimens with the theoretical density were prepared using the gas deposition method, and mechanical tests were carried out. In the elastic range, the Young's modulus found below 80 K for n-Au specimens with mean grain size of 26 -60 nm is higher than 92/100 of the bulk value, suggesting that the Young's modulus in the grain boundary region is higher than 70/100 of the bulk value. Above 200 K, anelastic strain due to a certain relaxation in the grain boundary region increases with increasing temperature, giving a decrease in the Young's modulus. Plasticity tests were made near room temperature for n-Au specimens with mean grain size of l5--60 nm. The Hall Petch relationship is observed in the Vickers microhardness tests with a holding time of l0 s, and creep deformation proceeds in quasi-static tensile tests for l03--l05 s, indicating that the preferable plastic deformation process near room
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