We analyze the influences of interstitial atoms on the generalized stacking fault energy （GSFE）, strength, and ductility of Ni by first-principles calculations. Surface energies and GSFE curves are calculated for t...We analyze the influences of interstitial atoms on the generalized stacking fault energy （GSFE）, strength, and ductility of Ni by first-principles calculations. Surface energies and GSFE curves are calculated for the （112） （111） and / 101） （ 1 1 1） systems. Because of the anisotropy of the single crystal, the addition of interstitials tends to promote the strength of Ni by slipping along the （10T） direction while facilitating plastic deformation by slipping along the （115） direction. There is a different impact on the mechanical behavior of Ni when the interstitials are located in the slip plane. The evaluation of the Rice criterion reveals that the addition of the interstitials H and O increases the brittleness in Ni and promotes the probability of cleavage fracture, while the addition of S and N tends to increase the ductility. Besides, P, H, and S have a negligible effect on the deformation tendency in Ni, while the tendency of partial dislocation is more prominent with the addition of N and O. The addition of interstitial atoms tends to increase the high-energy barrier γmax, thereby the second partial resulting from the dislocation tends to reside and move on to the next layer.展开更多
Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materialsin fusion reactor have been investigated. The results show that the high temperature strength andthe creep fracture life of Fe-Cr-Mn(W, V) st...Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materialsin fusion reactor have been investigated. The results show that the high temperature strength andthe creep fracture life of Fe-Cr-Mn(W, V) steels can be effectively improved through (C+N)complex-strengthening, so can be the high temperature ductility. The strength and ductility of thesteels are superior to that of SUS316 steels and JPCAS below 673 K. The relationship betweenstrength, ductility and the formation temperature is related to the evolution of deformationmicrostructure. The fracture and microstructure observation above 673 K indicates that the main wayto further improve ductility at high temperature is the control of carbide coarsening at the grainboundaries.展开更多
基金supported by the National Natural Science Foundation of China(Grant No 51371123)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.2013140211003)+1 种基金the Natural Science Foundation of Shanxi Science Technological Commission,China(Grant No.2014011002)the Scientific and Technological Research Program of Chongqing Municipal Education Commission,China(Grant No.KJ131315)
文摘We analyze the influences of interstitial atoms on the generalized stacking fault energy （GSFE）, strength, and ductility of Ni by first-principles calculations. Surface energies and GSFE curves are calculated for the （112） （111） and / 101） （ 1 1 1） systems. Because of the anisotropy of the single crystal, the addition of interstitials tends to promote the strength of Ni by slipping along the （10T） direction while facilitating plastic deformation by slipping along the （115） direction. There is a different impact on the mechanical behavior of Ni when the interstitials are located in the slip plane. The evaluation of the Rice criterion reveals that the addition of the interstitials H and O increases the brittleness in Ni and promotes the probability of cleavage fracture, while the addition of S and N tends to increase the ductility. Besides, P, H, and S have a negligible effect on the deformation tendency in Ni, while the tendency of partial dislocation is more prominent with the addition of N and O. The addition of interstitial atoms tends to increase the high-energy barrier γmax, thereby the second partial resulting from the dislocation tends to reside and move on to the next layer.
文摘Fe-Cr-Mn(W, V) austenite steels used as low radioactive structural materialsin fusion reactor have been investigated. The results show that the high temperature strength andthe creep fracture life of Fe-Cr-Mn(W, V) steels can be effectively improved through (C+N)complex-strengthening, so can be the high temperature ductility. The strength and ductility of thesteels are superior to that of SUS316 steels and JPCAS below 673 K. The relationship betweenstrength, ductility and the formation temperature is related to the evolution of deformationmicrostructure. The fracture and microstructure observation above 673 K indicates that the main wayto further improve ductility at high temperature is the control of carbide coarsening at the grainboundaries.
