High-strength cold-formed hot continuous rolled steel plate and method of preparing the same

Abstract

The invention relates to a high-strength cold-forming hot-continuous-rolling steel plate and the manufacture method thereof, wherein, the chemical composition of the steel plate is as follows: 0.05wt percent to 0.10wt percent of C, 0.10wt percent to 0.50wt percent of Si, 1.0wt percent to 2.0wt percent of Mn, less than or equal to 0.025wt percent of P, less than or equal to 0.010wt percent of S, 0.03wt percent to 0.08wt percent of Nb, 0.05wt percent to 0.15wt percent of Ti, 0.10wt percent to 0.50wt percent of Mo, 0.0010wt percent to 0.0050wt percent of Ca, 0.01wt percent to 0.05wt percent of Al and the rest, Fe and other inevitable impurities; the technical process of the steel plate includes hot metal deep desulfurization to converter top and bottom blowing to secondary refining to continuous casting (machine cleaning) to hot charging hot feeding soaking pit to plate blank reheating to controlled rolling to controlled cooling to coiling to finishing. With the yield strength reaching 700 MPa, the steel plate has excellent mechanical property and processing properties such as welding and roll forming; meanwhile, because less alloying element is added during the manufacture process of the steel plate, the invention has low production cost and convenient operation during big production without adopting heat treatment processes such as tempering and quenching and tempering. The invention can be used in fields such as engineering machinery and structural parts and container for special vehicle and strongbox, etc.

Description

technical field

[0001] The invention relates to the field of low-alloy steel manufacturing, in particular to a high-strength cold-formed hot-rolled steel plate and a production method thereof. Background technique

[0002] In today's increasingly tense energy supply, enhancing the strength of materials and reducing the weight of components represents the development direction of structural steel. The application of high-strength steel can significantly reduce the weight of the components and the self-weight of the equipment, thereby reducing the fuel consumption of the equipment and improving the working efficiency of the equipment. Therefore, there is an urgent need for a steel with high strength and excellent comprehensive mechanical properties in the fields of mobile equipment such as containers, automobiles and railway vehicles.

[0003] After searching, it is found that the existing high-strength steel types have certain defects. For example, the patent (CN1651589A) "...

Examples

Embodiment Construction

[0024] According to the steel chemical composition requirement of the present invention, adopt pure steel smelting process, carry out top-bottom composite blowing in 300 tons of converters of steelworks, then carry out refining outside furnace, obtain chemical composition and see Table 1, surplus is Fe and unavoidable Inclusion. The continuous casting slab is sent to the hot rolling production line, the slab is heated to above 1200°C, two-stage controlled rolling and post-rolling water cooling and coiling are adopted, the rough rolling end temperature is 1000-1050°C, and the final rolling temperature is 850-950°C. Laminar cooling, cooling rate 5-15°C / s, coiling temperature 550-650°C, to produce hot-rolled sheets, the final thicknesses are: 3.2mm, 6mm, respectively, and the mechanical properties are shown in Table 2. At the same time, Table 2 and Table 3 also compare the invented steel with the related steel grades for which the aforementioned patents have been applied for. Amo...

technical field

[0001] The invention relates to the field of low-alloy steel manufacturing, in particular to a high-strength cold-formed hot-rolled steel plate and a production method thereof. Background technique

[0002] In today's increasingly tense energy supply, enhancing the strength of materials and reducing the weight of components represents the development direction of structural steel. The application of high-strength steel can significantly reduce the weight of the components and the self-weight of the equipment, thereby reducing the fuel consumption of the equipment and improving the working efficiency of the equipment. Therefore, there is an urgent need for a steel with high strength and excellent comprehensive mechanical properties in the fields of mobile equipment such as containers, automobiles and railway vehicles.

[0003] After searching, it is found that the existing high-strength steel types have certain defects. For example, the patent (CN1651589A) "...

Examples

Embodiment Construction

[0024] According to the steel chemical composition requirement of the present invention, adopt pure steel smelting process, carry out top-bottom composite blowing in 300 tons of converters of steelworks, then carry out refining outside furnace, obtain chemical composition and see Table 1, surplus is Fe and unavoidable Inclusion. The continuous casting slab is sent to the hot rolling production line, the slab is heated to above 1200°C, two-stage controlled rolling and post-rolling water cooling and coiling are adopted, the rough rolling end temperature is 1000-1050°C, and the final rolling temperature is 850-950°C. Laminar cooling, cooling rate 5-15°C / s, coiling temperature 550-650°C, to produce hot-rolled sheets, the final thicknesses are: 3.2mm, 6mm, respectively, and the mechanical properties are shown in Table 2. At the same time, Table 2 and Table 3 also compare the invented steel with the related steel grades for which the aforementioned patents have been applied for. Amo...