A method for manufacturing a metal sheet comprising pinching the metal sheet in rapid quenching between a pair of pinch rolls in the range where the temperature of the metal sheet is from (T.sub.Ms+150) (° C.) to (T.sub.Mf−150) (° C.), wherein the Ms temperature of the metal sheet is T.sub.Ms (° C.) and the Mf temperature thereof is T.sub.Mf (° C.), as well as a rapid quenching unit comprising a pair of pinch rolls capable of use in such a method.

To achieve a substantially uniform microstructure across a continuously cast thin metal strip, it is beneficial to cool a width of the strip to a substantially constant temperature before further cooling the strip to reach any desired phase transformation temperature. Accordingly, methods of continuously casting a thin metal strip may include moving the thin strip to a cooling section, the cooling section having a plurality of coolant discharge ports configured to discharge a flow of coolant along the thin strip; initially sensing the temperature of the thin strip to determine a temperature distribution across the width of the thin strip, and producing a sensor signal corresponding to a sensed temperature at each of the first plurality of locations; and individually controlling the cooling across a width of the thin strip by way of the plurality coolant discharge ports in each zone of a first row using the determined temperature distribution.

To achieve a substantially uniform microstructure across a continuously cast thin metal strip, it is beneficial to cool a width of the strip to a substantially constant temperature before further cooling the strip to reach any desired phase transformation temperature. Accordingly, methods of continuously casting a thin metal strip may include moving the thin strip to a cooling section, the cooling section having a plurality of coolant discharge ports configured to discharge a flow of coolant along the thin strip; initially sensing the temperature of the thin strip to determine a temperature distribution across the width of the thin strip, and producing a sensor signal corresponding to a sensed temperature at each of the first plurality of locations; and individually controlling the cooling across a width of the thin strip by way of the plurality coolant discharge ports in each zone of a first row using the determined temperature distribution.

The present invention belongs to the field of heat treatment for metal plate strips, and discloses a water spray system for heat treatment of metal plate strips and a control method. The system comprises a shunt water collector, sub-water supply pipelines, a control valve group and a control system. The control method comprises a water pressure regulating method and a water flow regulating method. The shunt water collector adopts multi-pipeline uniform flow design and realizes uniform shunt and constant pressure water supply. The sub-water supply pipelines are designed with three configuration modes of a control valve group in accordance with varieties and specifications of metal plate strips, rhythms of production and heat treatment technologies to realize dual closed-loop control of water pressure-water flow.

The present invention belongs to the field of heat treatment for metal plate strips, and discloses a water spray system for heat treatment of metal plate strips and a control method. The system comprises a shunt water collector, sub-water supply pipelines, a control valve group and a control system. The control method comprises a water pressure regulating method and a water flow regulating method. The shunt water collector adopts multi-pipeline uniform flow design and realizes uniform shunt and constant pressure water supply. The sub-water supply pipelines are designed with three configuration modes of a control valve group in accordance with varieties and specifications of metal plate strips, rhythms of production and heat treatment technologies to realize dual closed-loop control of water pressure-water flow.

Methods of selectively cooling and quenching surface regions of high-strength transformation induced plasticity (TRIP) steel are provided. The method may comprise selectively cooling at least one region of an exposed surface of a hot-formed press-hardened component comprising a high-strength steel. Prior to selective cooling, the component has a microstructure comprising≧about 5% by volume retained austenite in a matrix of martensite. The selective cooling is conducted at a temperature of≦about −40° C. and forms at least one quenched region comprising≦about 2% by volume austenite. The TRIP steel may be zinc-coated and having a surface coating comprising zinc and substantially free of liquid metal embrittlement (LME). Zinc-coated hot-formed press-hardened components, including automotive components, formed from such methods are also provided.

Methods of selectively cooling and quenching surface regions of high-strength transformation induced plasticity (TRIP) steel are provided. The method may comprise selectively cooling at least one region of an exposed surface of a hot-formed press-hardened component comprising a high-strength steel. Prior to selective cooling, the component has a microstructure comprising≧about 5% by volume retained austenite in a matrix of martensite. The selective cooling is conducted at a temperature of≦about −40° C. and forms at least one quenched region comprising≦about 2% by volume austenite. The TRIP steel may be zinc-coated and having a surface coating comprising zinc and substantially free of liquid metal embrittlement (LME). Zinc-coated hot-formed press-hardened components, including automotive components, formed from such methods are also provided.

Disclosed are a steel pipe having a three-layer structure and a manufacturing method thereof. The steel pipe includes a three-layer structure of bainite and martensite, which are formed by high-frequency induction heating thereby improving toughness to enhance crash performance of a vehicle. The steel pipe includes a bainite structure layer, a bainite and martensite dual-phase structure layer, and a martensite structure layer.

Disclosed are a steel pipe having a three-layer structure and a manufacturing method thereof. The steel pipe includes a three-layer structure of bainite and martensite, which are formed by high-frequency induction heating thereby improving toughness to enhance crash performance of a vehicle. The steel pipe includes a bainite structure layer, a bainite and martensite dual-phase structure layer, and a martensite structure layer.

This relates to a process for manufacturing a recovery annealed coated steel substrate for packaging applications and a packaging steel product produced thereby.