2/mmc、P42/nnm和I4/mmm。計(jì)算結(jié)果表明，ε氫化物的生成焓最低，并提出了γ→δ→ε的相變順序。與α-Zr相比，氫化物的c軸晶格常數(shù)變小，γ、δ和ε單位胞的膨脹體積分別為12.1%、14.8%和17.9%。3種氫化物的計(jì)算彈性模量（E）均低于α-Zr，但彈性各向異性均高于α-Zr。通過(guò)納米壓痕實(shí)驗(yàn)分析了α-Zr基體和δ氫化物的彈性性能，結(jié)果表明，α-Zr基體和δ氫化物的E分別為116.88和111.01 GPa。因此，在氫化物/基體界面的氫化物側(cè)容易發(fā)生應(yīng)力集中，氫化物容易成為裂紋源，導(dǎo)致鋯合金發(fā)生脆性斷裂。;The structure and elastic properties of α-Zr and its hydrides were investigated by first-principle calculations and experimental methods. Considering all possible H-atom configurations, different phase models of hydrides were constructed. Results show that the stable structures of γ, δ and ε hydrides are P42/mmc, P42/nnm and I4/mmm, respectively. Calculation results suggest that ε hydride has the lowest formation enthalpy, and the phase transition sequence of γ → δ → ε is proposed. Compared with those of α-Zr, the c-axis lattice constants of hydrides become smaller, and the expansion volumes of γ, δ and ε unit cell are 12.1%, 14.8% and 17.9%, respectively. The calculated elastic modulus (E) of the three hydrides are lower than that of α-Zr, but their elastic anisotropy is higher than that of α-Zr. The elastic properties of α-Zr matrix and δ hydride were analyzed by nanoindentation experiment and the results show that E of the α-Zr matrix and δ hydride is 116.88 and 111.01 GPa, respectively. Therefore, the stress concentration is easy to occur on the hydride sides near the hydrides/matrix interface, so the hydrides are more likely to be the sources of crack and cause brittle fracture of zirconium alloys."/>