摘要:
A hot rolled steel sheet with a high strength and a distinguished formability, and a process for producing the same are disclosed. The steel sheet comprises 0.15 to 0.4% by weight of C, 0.5 to 2.0% by weight of Si, and 0.5 to 2.0% by weight of Mn, the balance being iron and inevitable impurities, and has a microstructure composed of ferrite, bainite and retained austenite phases with the ferrite phase being a ratio (V.sub.PF /d.sub.PF) of polygonal ferrite volume fraction V.sub.PF (%) to polygonal ferrite average grain size d.sub.PF (.mu.m) of 7 or more and the retained austenite phase being contained in an amount of 5% by volume or more on the basis of the total phases. The steel sheet can be produced with a high productivity and without requiring special alloy elements.
摘要:
A hot rolled steel sheet with a high strength and a distinguished formability, and a process for producing the same are disclosed. The steel sheet comprises 0.15 to 0.4% by weight of C, 0.5 to 2.0% by weight of Si, and 0.5 to 2.0% by weight of Mn, the balance being iron and inevitable impurities, and has a microstructure composed of ferrite, bainite and retained austenite phases with the ferrite phase being in a ratio (V.sub.PF /d.sub.PF) of polygonal ferrite volume fraction V.sub.PF (%) to polygonal ferrite average grain size d.sub.PF (.mu.m) of 7 or more and the retained austenite phase being contained in an amount of 5% by volume or more on the basis of the total phases. The steel sheet can be produced with a high productiviity and without requiring special alloy elements.
摘要:
A high yield ratio-type, hot rolled high strength steel sheet excellent in both formability and spot weldability, containing not less than 5% of retained austenite, and a process for producing the same are provided. The steel sheet contains 0.05 to less than 0.15% by weight or 0.15 to less than 0.30% by weight of C, 0.5 to 3.0% by weight of Si, 0.5 to 3.0% by weight of Mn, more than 1.5 to 6.0% by weight of Si and Mn in total, not more than 0.02% by weight of P, no more than 0.01% by weight of S, and 0.005 to 0.10% by weight of Al, the balance essentially being Fe, and is composed of three phases of ferrite, bainite and retained austenite as a microstructure, and having a ratio (V.sub.F /d.sub.F) of ferrite volume fraction (V.sub.F) to ferrite grain size (d.sub.F) of not less than 20 (not less than 7 in case of 0.15 to less than 0.30% by weight of C), a volume fraction of retained austenite having grain sizes of not more than 2 .mu.m being 5% or more, a yield ratio (YR) of not less than 60%, a strength-ductility balance (tensile strength.times.total elongation) of not less than 2,000 (kgf/mm.sup.2.%), an enlargement ratio (d/d.sub.o) of not less than 1.4 (not less than 1.1 in case of 0.15 to less than 0.30% by weight of C), and a uniform elongation of not less than 15% (not less than 10% in case of 0.15 to less than 0.30% by weight of C).
摘要:
The object of the present invention is to provide high-strength steel sheets exhibiting high impact energy absorption properties, as steel sheets to be used for shaping and working into such parts to front side members which absorb impact energy upon collision, as well as a method for their production. The high-strength steel sheets of the invention which exhibit high impact energy absorption properties are press formable high-strength steel sheets with high flow stress during dynamic deformation characterized in that the microstructure of the steel sheets in their final form is a composite microstructure of a mixture of ferrite and/or bainite, either of which is the dominant phase, and a third phase including retained austenite at a volume fraction between 3% and 50%, wherein the difference between the static tensile strength as when deformed in a strain rate range of 5×10−4˜5×10−3 (l/s) after pre-deformation at an equivalent strain of greater than 0% and less than or equal to 10%, and the dynamic tensile strength &sgr;d when deformed at a strain rate of 5×102˜5×103 (l/sec) after the pre-deformation, i.e. &sgr;d−&sgr;s, is at least 60 MPa, and the work hardening coefficient between 5% and 10% of a strain is at least 0.130.
摘要:
The object of the present invention is to provide high-strength steel sheets exhibiting high impact energy absorption properties, as steel materials, to be used for shaping and working into such parts as front side members of automobiles which absorb impact energy upon collision, as well as a method for their production. The high-strength steel sheets of the invention which exhibit high impact energy absorption properties are high-strength steel sheets with high flow stress during dynamic deformation characterized in that the microstructure of the steel sheets in their final form is a composite microstructure of a mixture of ferrite and/or bainite, either of which is the dominant phase, and a third phase including retained austenite at a volume fraction between 3% and 50%, wherein the average value &sgr;dyn (MPa) of the flow stress in the range of 3˜10% of equivalent strain when deformed in a strain rate range of 5×102˜5×103 (1/sec) after pre-deformation of greater than 0% and less than or equal to 10% of equivalent strain, satisfies the inequality: &sgr;dyn≧0.766×TS+250 as expressed in terms of the maximum stress TS (MPa) in the static tensile test as measured in a strain rate range of 5×10−4˜5×10−3 (1/s) without deformation, and the work hardening coefficient between 1% and 5% of a strain is at least 0.080.
摘要:
In a vehicle remote operating system remotely operating a host vehicle VM from a portable terminal 200, a main control unit 112 of an ECU 110 of an in-vehicle device 100 determines an dispatch position of the host vehicle VM on the basis of a parking position of the host vehicle VM and a position of a user U who intends to board the host vehicle VM. Due to this, it becomes possible to dispatch the host vehicle VM according to the parking position of the host vehicle VM and the position of the user U, and convenience is improved in dispatch operation and boarding of the host vehicle VM.
摘要:
A parking assistance apparatus includes a display unit that displays an image of a scene behind a host vehicle. At least when the host vehicle moves forward or when the host vehicle is stopped, the display unit displays an indication including a plurality of kinds of trajectories along which the host vehicle is able to back up from a point at which the host vehicle is currently positioned, in a manner such that the indication is superimposed on the image of the scene behind the host vehicle.
摘要:
A parking assistance apparatus includes a display unit that displays an image of a scene behind a host vehicle. At least when the host vehicle moves forward or when the host vehicle is stopped, the display unit displays an indication including a plurality of kinds of trajectories along which the host vehicle is able to back up from a point at which the host vehicle is currently positioned, in a manner such that the indication is superimposed on the image of the scene behind the host vehicle.
摘要:
In a vehicle remote operating system remotely operating a host vehicle VM from a portable terminal 200, a main control unit 112 of an ECU 110 of an in-vehicle device 100 determines an dispatch position of the host vehicle VM on the basis of a parking position of the host vehicle VM and a position of a user U who intends to board the host vehicle VM. Due to this, it becomes possible to dispatch the host vehicle VM according to the parking position of the host vehicle VM and the position of the user U, and convenience is improved in dispatch operation and boarding of the host vehicle VM.
摘要:
In a vehicle remote operating system remotely operating a host vehicle VM from a portable terminal 200, a main control unit 112 of an ECU 110 of an in-vehicle device 100 determines an dispatch position of the host vehicle VM on the basis of a parking position of the host vehicle VM and a position of a user U who intends to board the host vehicle VM. Due to this, it becomes possible to dispatch the host vehicle VM according to the parking position of the host vehicle VM and the position of the user U, and convenience is improved in dispatch operation and boarding of the host vehicle VM.