| 摘要 |
PROBLEM TO BE SOLVED: To produce shape steel having excellent collision resistance, and whose absorbing capability of energy in case of collision can be increased without increasing the cost caused by the addition of alloy elements, or the like, and without changing the design for ship structure, and to provide its production method. SOLUTION: This shape steel having excellent collision resistance has a steel composition satisfying the carbon equivalent (Ceq) defined by the following formula (1) of <=0.38 mass% and has a steel structure composed of ferritic phases and hard phases, in which the phase fraction of the ferritic phases is >=70%, hardness is <=150 Hv, the average grain size is >=5μm, also, the average of the aspect ratios of the hard phases or the average of the aspect ratios of the hard phase bands in which the hard phases are ranged is >=1.5; wherein, in the formula (1), each elemental symbol is the content expressed by mass%: Ceq=C+Mn/6+(Cr+Mo+V)5+(Ni+Cu)/15...(1).
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