STEEL SHEET HAVING HIGH YOUNG'S MODULUS, HOT-DIP GALVANIZED STEEL SHEET USING THE SAME, ALLOYED HOT-DIP GALVANIZED STEEL SHEET, STEEL PIPE HAVING HIGH YOUNG'S MODULUS, AND METHODSFOR MANUFACTURING THESE

摘要

An embodiment of a high Young~s modulus steel sheet, wherein it has a chemic al composition, in mass %, that C: 0.0005 to 0.30 %, Si: 2.5 % or less, Mn: 2.7 to 5.0 %, P: 0.15 % or less, S: 0.015 % or less, Mo: 0.15 to 1.5 %, B: 0.000 6 to 0.01%, Al: 0.15 % or less, and the balance: Fe and inevitable impurities, and wherein both or any of {110}223 and {110}111 in a layer at 1/8 of the thickness of the sheet have a pole density of 10 or more and a Young~ modulu s in the rolling direction of more than 230 GPa: and another embodiment of a high Young~s modulus steel sheet, wherein it has a chemical composition, in mass %, that C: 0.0005 to 0.30 %, Si: 2.5 % or less, Mn: 0.1 to 5.0 %, P: 0. 15 % or less, S: 0.015 % or less, Al: 0.15 % or less, N: 0.01 % or less, and further comprises 0.015 to 1.91 % by mass in total of one or more of Mo: 0.0 05 to 1.5 %, Nb: 0.005 to 0.20 %, Ti: (48/14 X N)% to 0.2 % and B: 0.0001 to 0.01%, and the balance: Fe and inevitable impurities, and wherein {110}2 23 and/or {110}111 in a layer at 1/8 of the thickness of the sheet have a pole density of 10 or more and a Young~ modulus in the rolling direction of more than 230 GPa.