Abstract: The present invention provides a steel sheet excellent in workability, which may be used for components of an automobile or the like, and a method for producing the same. More specifically, according to one exemplary embodiment of the present invention, a steel sheet excellent in workability, including in mass, 0.08 to 0.25% C, 0.001 to 1.5% Si, 0.01 to 2.0% Mn, 0.001 to 0.06% P, at most 0.05% S, 0.001 to 0.007% N, 0.008 to 0.2% Al, at least 0.01% Fe. The steel sheet having an average r-value of at least 1.2, an r-value in the rolling direction of at least 1.3, an r-value in the direction of 45 degrees to the rolling direction of at least 0.9, and an r-value in the direction of a right angle to the rolling direction of at least 1.2.

Abstract: The present invention provides a steel sheet excellent in workability, which may be used for components of an automobile or the like, and a method for producing the same. More specifically, according to one exemplary embodiment of the present invention, a steel sheet excellent in workability, including in mass, 0.08 to 0.25% C, 0.001 to 1.5% Si, 0.01 to 2.0% Mn, 0.001 to 0.06% P, at most 0.05% S, 0.001 to 0.007% N, 0.008 to 0.2% Al, at least 0.01% Fe. The steel sheet having an average r-value of at least 1.2, an r-value in the rolling direction of at least 1.3, an r-value in the direction of 45 degrees to the rolling direction of at least 0.9, and an r-value in the direction of a right angle to the rolling direction of at least 1.2.

Abstract: One aspect of the steel sheet having high Young's modulus includes in terms of mass %, 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: 0.0006 to 0.01%, and Al: 0.15% or less, with the remainder being Fe and unavoidable impurities, wherein one or both of {110}<223> pole density and {110}<111> pole density in the ? sheet thickness layer is 10 or more, and a Young's modulus in a rolling direction is more than 230 GPa. Another aspect of the steel sheet having high Young's modulus includes, in terms of mass %, 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 one or two or more of Mo: 0.005 to 1.5%, Nb: 0.005 to 0.20%, Ti: at least 48/14×N (mass %) and 0.2% or less, and B: 0.0001 to 0.01%, at a total content of 0.015 to 1.

Abstract: A high-strength hot-rolled steel sheet excellent in shape fixability having ferrite or bainite as the phase of the largest volume percentage, satisfying all of the following at least at ½ sheet thickness: a mean value of X-ray random intensity ratio in the orientation component group of {100}<011> to {223}<110> to X-ray random diffraction intensity ratio of at least 2.5; a mean value of X-ray random intensity ratio in the three crystal orientation components of {554}<225>, {111}<112>, and {111}<110> to X-ray random diffraction intensity ratio of 3.5 or less; an X-ray intensity ratio to X-ray random diffraction intensity ratio at {100}<011> of at least the X-ray random intensity to X-ray random diffraction intensity ratio at {211}<011>; and an X-ray random intensity ratio to X-ray random intensity ratio diffraction intensity ratio at {100}<011> of at least 2.

Abstract: High yield ratio high-strength thin steel sheet D superior in weldability and ductility characterized by; being comprised of steel containing, by mass %, C: over 0.030 to less than 0.10%, Si: 0.30 to 0.80%, Mn: 1.7 to 3.2%, P: 0.001 to 0,02%, S: 0.0001 to 0.006%, Al: 0.060% or less, N: 0.0001 to 0.0070%, containing further c Ti: 0.01 to 0.055%, Nb: 0.012 to 0.055%, Mo: 0.07 to 0.55%, B: 0.0005 to 0.0040%, and simultaneously statisfying 1.1?14×Ti(%)+20×Nb(%)+3×Mo(%)+300×B(%)?3.7, the balance comprised of iron and unavoidable impurities, and having a yield ratio of 0.64 to less than 0.92, a TS×El of 3320 or more, an YR×TS×El1/2 of 2320 or more, and a maximum tensile strength (TS) of 780 MPa or more.

Abstract: A ferritic steel sheet wherein a mean value of X-ray random intensity ratios of a group of {100}<011> to {223}<110> orientations is 3.0 or more and a mean value of X-ray random intensity ratios of three crystal orientations of {554}<225>, {111}<112>, and {111}<110> is 3.5 or less and further at least one of the r values in a rolling direction and a direction at a right angle of that is 0.7 or less.

Abstract: The present invention is a high strength steel pipe excellent in formability in hydroforming and similar forming methods, characterized by: containing, in mass, C of 0.0005 to 0.30%, Si of 0.001 to 2.0%, Mn of 0.01 to 3.0% and appropriate amounts of other elements if necessary, with the balance consisting of Fe and unavoidable impurities; and an average for the ratios of the X-ray strength in the orientation component group of {110}<110> to {111}<110> to random X-ray diffraction strength on a plane at the wall thickness center being 2.0 or more and/or a ratio of the X-ray strength in the orientation component of {110}<110> to random X-ray diffraction strength on the plane at the wall thickness center being 3.0 or more.

Abstract: The present invention provides a steel sheet excellent in workability, which may be used for components of an automobile or the like, and a method for producing the same. More specifically, according to one exemplary embodiment of the present invention, a steel sheet excellent in workability, including in mass, 0.08 to 0.25% C, 0.001 to 1.5% Si, 0.01 to 2.0% Mn, 0.001 to 0.06% P, at most 0.05% S, 0.001 to 0.007% N, 0.008 to 0.2% Al, at least 0.01% Fe. The steel sheet having an average r-value of at least 1.2, an r-value in the rolling direction of at least 1.3, an r-value in the direction of 45 degrees to the rolling direction of at least 0.9, and an r-value in the direction of a right angle to the rolling direction of at least 1.2.

Abstract: The present invention provides a thin steel sheet, for automobile use, excellent in notch-fatigue strength, and a method for producing said steel sheet. Specifically, the present invention is a thin steel sheet for automobile use excellent in notch-fatigue strength, said steel sheet containing, in mass, 0.01 to 0.3% C, 0.01 to 2% Si, 0.05 to 3% Mn, 0.1% or less P, 0.01% or less S and 0.005 to 1% Al, with the balance consisting of Fe and unavoidable impurities, characterized in that, on a plane at an arbitrary depth within 0.

Abstract: To provide a steel sheet excellent in painting bake hardenability and anti aging property at room temperature: containing, in mass, 0.0001 to 0.20% of C, 2.0% or less of Si, 3.0% or less of Mn, 0.15% or less of P, 0.015% or less of S, and, in addition, 010% or less of Al and 0.001 to 0.10% of N so as to satisfy the expression 0.52Al/N<5 and, further, one or more of 2.5% or less of Cr, 1.0% or less of Mo and 0.1% or less of V so as to satisfy the expression (Cr+3.5MO+39V) ≧0.1, with the balance consisting of Fe and unavoidable impurities; having the value of BH170, evaluated after applying a 2% tensile deformation and then a heat treatment at 170° C. for 20 min., being 45 MPa or more, and any of the value of BH160, evaluated after applying a 2% tensile deformation and then a heat treatment at 160° C. for 10 min., and the value of BH150, evaluated after applying a 2% tensile deformation and then a heat treatment at 150° C. for 10 min.

Abstract: A ferritic steel sheet wherein a mean value of X-ray random intensity ratios of a group of {100}<011> to {223}<110> orientations is 3.0 or more and a mean value of X-ray random intensity ratios of three crystal orientations of {554}<225>, {111}<112>, and {111}<110> is 3.5 or less and further at least one of the r values in a rolling direction and a direction at a right angle of that is 0.7 or less.

Abstract: The present invention provides a steel pipe excellent in formability during hydraulic forming and the like and a method to produce the same, and more specifically: a steel pipe excellent in formability having an r-value of 1.4 or larger in the axial direction of the steel pipe, and the property that the average of the ratios of the X-ray intensity in the orientation component group of {110}<110> to {332}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 3.5 or larger, and/or the ratio of the X-ray intensity in the orientation component of {110}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 5.

Abstract: The present invention provides a steel pipe excellent in formability during hydraulic forming and the like and a method to produce the same, and more specifically: a steel pipe excellent in formability having an r-value of 1.4 or larger in the axial direction of the steel pipe, and the property that the average of the ratios of the X-ray intensity in the orientation component group of {110}<110> to {332}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 3.5 or larger, and/or the ratio of the X-ray intensity in the orientation component of {110}<110> on the plane at the center of the steel pipe wall thickness to the random X-ray intensity is 5.

Abstract: The present invention is a high strength steel pipe excellent in formability in hydroforming and similar forming methods, characterized by: containing, in mass, C of 0.0005 to 0.30%, Si of 0.001 to 2.0%, Mn of 0.01 to 3.0% and appropriate amounts of other elements if necessary, with the balance consisting of Fe and unavoidable impurities; and an average for the ratios of the X-ray strength in the orientation component group of {110}<110> to {111}<110> to random X-ray diffraction strength on a plane at the wall thickness center being 2.0 or more and/or a ratio of the X-ray strength in the orientation component of {110}<110> to random X-ray diffraction strength on the plane at the wall thickness center being 3.0 or more.

Abstract: To provide a steel sheet excellent in painting bake hardenability and anti aging property at room temperature: containing, in mass, 0.0001 to 0.20% of C, 2.0% or less of Si, 3.0% or less of Mn, 0.15% or less of P, 0.015% or less of S, and, in addition, 010% or less of Al and 0.001 to 0.10% of N so as to satisfy the expression 0.52Al/N<5 and, further, one or more of 2.5% or less of Cr, 1.0% or less of Mo and 0.1% or less of V so as to satisfy the expression (Cr+3.5MO+39V) ≧0.1, with the balance consisting of Fe and unavoidable impurities; having the value of BE170, evaluated after applying a 2% tensile deformation and then a heat treatment at 170° C. for 20 min., being 45 MPa or more, and any of the value of BH160, evaluated after applying a 2% tensile deformation and then a heat treatment at 160° C. for 10 min., and the value of BH150, evaluated after applying a 2% tensile deformation and then a heat treatment at 150° C. for 10 min.

Abstract: According to the present invention, an ultra low carbon steel with Nb, Ti, or Nb-Ti added thereto is used as a material, and (% S as MnS)/(total S content) is regulated to not more than 0.2 with (% C as carbosulfide)/(total C content) being regulating to not more than 0.7, thereby efficiently precipitating carbosulfide in a .gamma. temperature region during hot rolling and thus reducing the amount of C in solid solution to ensure the homogeneity of the material over the whole length of a coil and to markedly improve the workability.

Abstract: The present invention provides a cold-rolled steel sheet and a hot-dip galvanized steel sheet having good bake hardenability, non-aging properties at room temperature and good formability and a process for producing the same. An extra low carbon steel or an extra low carbon steel containing at least one element selected from Ti and Nb is annealed at a temperature of not lower than the AC.sub.3 transformation point to bring the structure after annealing to a structure of low-temperature transformation products. This makes it possible to provide a steel sheet that has a combination of high paint-bake hardenability and non-aging properties at room temperature and is excellent also in formability in respect of average r value (deep drawability) and elongation (punch stretchability). In particular, with respect to paint-bake hardenability, a BH property on a high level up to about 10 kgf/mm.sup.

Abstract: The present invention provides a non-aging at room temperature ferritic single-phase cold-rolled steel sheet or hot-dip galvanized steel sheet for deep drawing and having excellent fabrication embrittlement resistance and paint-bake hardenability, by heating a slab comprising, in terms of % by weight, 0.0001 to 0.0015% of C, not more than 1.2% of Si, 0.03 to 3.0% of Mn, 0.01 to 0.15% of P, 0.0010 to 0.020% of S, 0.005 to 0.1% of Al, 0.0001 to 0.0080% of N and 0.0001 to 0.0030% of B and optionally 0.1 to 3% of Cr with the balance consisting of Fe and unavoidable impurities, hot-rolling the heated slab at a finishing temperature of not lower than (Ar.sub.3 --100).degree. C., cooling the hot-rolled coil within 1 sec after the hot rolling at a rate of not less than 50.degree. C./sec from the finishing temperature to a temperature in the range of from 600.degree. to 750.degree. C.

Abstract: The present invention provides a cold rolled steel sheet and a hot dip zinc-coated cold rolled steel sheet excellent in paint bake hardenability, non-aging properties and formability, and a process for producing the same. In the present invention, an extremely low carbon steel or extremely low carbon steel containing at least one element selected from the group consisting of Ti and Nb is used as a base steel, and Mn and Cr are positively added thereto, whereby the resultant steel has a mixed structure after annealing. Accordingly, there can be obtained a steel sheet having both a high paint bake hardenability and non-aging properties, and being excellent in formability such as an average r-value (deep drawability). With regard to the paint bake hardenability, the present invention may provide a cold rolled steel sheet and a hot dip zinc-coated cold rolled steel sheet to which paint bake hardening may be optionally imparted in an amount as large as about 10 kgf/mm.sup.

Abstract: A high-strength cold-rolled steel strip or a molten zinc-plated high-strength cold-rolled steel strip which have a low yield strength, containing, by weight, of 0.0005-0.01% C, not more than 0.8% Si, more than 0.5% but not more than 3.0% Mn, 0.01-0.12%: P. 0.0010-0.015% S, 0.01-0.1% Al, 0.0005-0.0060% N, not less than 0.0001% but less than 0.005-0.1% the content of Nb being made to satisfy Nb .gtoreq.93/12 (C-0.0015), or instead of 0.005-0.1% Nb, 0.0005-0.1% Ti and 0.003-0.1% Nb, the content of Nb and the content of Ti being made satisfy, Ti.gtoreq.3.42N, and the balance Fe and incidental impurities is provided. Another steel strip or molten zinc-plated strip is provided that contains 0.2-3.0% Cr but does not require B, and includes both Ti and Nb. The method of producing such is also provided.