Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Yamaguchi, Masatake; Kameda, Jun*
no journal, ,
Atomistic mechanisms of solute-segregation-induced cracking in alloy steel have been studied by the combined analysis of first-principles calculations using VASP code and fracture mechanics experiments. This study indicates how the grain boundary (GB) cohesive energy (
) is affected by the segregation of immobile and mobile solute, such asphosphorous (P), tin (Sn) and antimony (Sb) as well as hydrogen (H). The reduction of 2
, associated with suppressing plastic work (
), facilitates the growth of nucleated GB microcracks, leading to a large fracture toughness loss. For rapid GB crack growth caused by the segregation of immobile P, Sn and Sb (temper embrittlement), the coverage on one of the two fracture surfaces maintains a half of the GB coverage. On the other hand, the mobile segregation of H promotes slow GB cracking by maintaining the condition of constant chemical potential between the surface and GB.
Sakai, Seiji; Matsumoto, Yoshihiro; Entani, Shiro; Otomo, Manabu; Avramov, P.
no journal, ,
by the dynamic extinction of neutron radiationLiss, K. D.; Kabra, S.*; Thoennessen, L.*; Harjo, S.; Reid, M.*; Yan, K.*; Harrison, R.*; Dippenaar, R. J.*
no journal, ,
Yamashita, Shinichiro; Sekio, Yoshihiro; Sakaguchi, Norihito*; Shibayama, Tamaki*; Watanabe, Seiichi*; Kokawa, Hiroyuki*
no journal, ,
Recent grain boundary structure studies have shown that optimal distribution of a high frequency of coincidence site lattice boundaries and consequent discontinuity of random boundary network in the material is one of very effective methods to enhance the intergranular corrosion resistance. This advantageous property, one of important ones for structural material of nuclear reactor, can be obtained through simple thermomechanical treatment process without any change of original chemical composition. In this study, grain boundary character distribution(GBCD)-optimized Ni-based alloy (PE16) has been developed as a prospective high-performance nuclear reactor material by grain boundary engineering processing, and then tensile behavior of GBCD-optimized Ni-based alloy was investigated to evaluate the effect of grain boundary engineering processing on mechanical property. The result of tensile test at room temperature showed that tensile strength of GBCD-optimized PE16 was somewhat lower than that of as-received PE16. However, no significant change was confirmed in elongation property. Details on tensile behavior analyses would be discussed in the conference.
Al foils for methane steam reformingXu, Y.*; Ma, Y.*; Sakurai, Junya*; Demura, Masahiko*; Hirano, Toshiyuki*; Teraoka, Yuden; Yoshigoe, Akitaka
no journal, ,