PURPOSE: To obtain a steel plate excellent in damping characteristic against vibrations caused by wind, earthquake, etc., when used for steel structures, such as bridge and buildings.
CONSTITUTION: In an integrated steel plate having a surface layer part composed of dead soft steel and an inner layer part composed of high tensile strength steel, the surface layer has a composition consisting of ≤0.01% C, ≤0.05% Si, ≤0.5% Mn, 0.005-0.07% Al, and the balance Fe with impurities and containing, if necessary, one or more elements among Ti, Nb, and Ca. The inner layer has a composition consisting of 0.04-0.2% C, 0.05-0.4% Si, 0.5-1.5% Mn, 0.2-1.5% Cr, 0.1-1.0% Mo, 0.005-0.08% Al, and the balance Fe with impurities and further containing, if strength and toughness are necessary, one or more elements among Ni, Cu, Nb, V, Ti, B, and Ca. By this method, damping characteristic against the vibration load within the range of elasticity of the inner layer can be improved by the absorption of energy due to the plastic deformation of the surface layer.
TANABE KOJI
KAWAI YOSHIMICHI
UNO NOBUYOSHI
