表層超細粒鋼板の座屈・塑性崩壊強度特性に関する一考察

概要

論文の詳細を見る
A new type of steel plate with high fracture toughness has been developed by further improving TMCP (Thermo Mechanical Control Process) technology. The steel plate possesses S__-urface layers of U__-ltra F__-ine grain microstructure (SUF) of 1 to 3 micrometers in diameter, of which thickness is one sixth of the plate thickness. The SUF provides various advantages: for example, the SUF makes it difficult for unstable brittle crack to penetrate into the plate from its surface, dramatically improves crack arresting toughness against unstable brittle crack propagation, and so on. In the present paper, series of column buckling tests are conducted using SUF steel plate. Elastoplastic large deflection analysis is also performed on the column specimens by FEM. Then, the same analyses are carried out both on isolated and stiffened plates in a ship structure. The results suggest the followings: (1) Initial yielding strength and ultimate strength of columns subjected to axial compression are increased by 4 through 10% owing to SUF. (2) Initial yielding strength and ultimate strength of isolated plates under thrust are increased by 5 through 16% owing to SUF. (3) When stiffened plates are made of SUF plates, their compressive ultimate strength is increased, and the start of the strength reduction in the post-ultimate strength range is delayed.
社団法人日本船舶海洋工学会の論文
1997-03-29