Method for manufacturing thick-specification high-precision cold-rolled low-alloy high-strength steel strip

Abstract

The invention discloses a method for manufacturing a thick-specification high-precision cold-rolled low-alloy high-strength steel strip. The thickness of the thick-specification high-precision cold-rolled low-alloy high-strength steel strip is greater than 3 millimeters, and the mechanical property of relevant standard requirements are met by the cold-rolled steel strip. The dimensional precisionof the thick-specification high-precision cold-rolled low-alloy high-strength steel strip reaches the cold rolling standard PT.B level. The depth of the decarburized layer and the intergranular oxidation later of the thick-specification high-precision cold-rolled low-alloy high-strength steel strip is less than 15 mu m. The grain size of the thick-specification high-precision cold-rolled low-alloyhigh-strength steel strip reaches level 6 and above. The thick-specification high-precision cold-rolled low-alloy high-strength steel strip has a quite good automobile application background and realistic cutting-in of the market and has a quite good guiding function on conducting of industrialization exploration on the basis of sufficient research and development and broad prospects; the methodis new-generation cold rolling technology application research, nationalization of relevant industries can be driven, and the international status in the technological frontier of our nation is pushed; and the method has great significances on comprehensive promoting of steel deep machining and special type-demanded steel nationalization.

Description

technical field [0001] The invention relates to the technical field of high-precision cold-rolled new materials, in particular to a method for manufacturing thick gauge high-precision cold-rolled low-alloy high-strength steel strips. Background technique [0002] The most dynamic, creative and fastest-growing steel structural materials are low-alloy high-strength steels. Adding a small amount (single or composite addition of less than 0.1%) alloying elements (vanadium, niobium, titanium, etc.) to the steel forms relatively stable carbides and nitrides, thereby producing grain refinement and precipitation in the steel Strengthening effect, the steel whose yield strength is 2 to 3 times higher than that of carbon steel and carbon-manganese steel is called low-alloy high-strength steel. [0003] With the rapid growth of China's steel output, the adjustment of product structure has always been an important task for China's steel industry. By using high-strength low-alloy steel...

AI Technical Summary

Problems solved by technology

Due to the limitation of the production capacity of continuous annealing equipment, it is impossible to realize the production of cold-rolled low-alloy high-strength steel above 3.0mm, and the production of high-precision parts is often impossible for hot-rolled products of corresponding grades due to insufficient dimensional accuracy

With the continuous development of industrial fields such as automobiles and machinery, the demand for thick-gauge, high-strength, low-alloy steel continues to increase. Most of them can only meet production needs by importing relevant materials. It satisfies the needs of the domestic market very well, so some national energy companies use hot-rolled products to meet customer needs after flattening, but this also brings technical problems such as welding deformation, bending cracks, etc.