Thin-gauge riffled plate/strip and manufacturing method thereof

Abstract

The invention discloses a thin-gauge riffled plate / strip and a manufacturing method thereof. Microalloy elements such as B are selectively added into steel; the alkalinity of slag, the type and melting point of inclusions in the steel, the content of free oxygen in molten steel and the content of acid-soluble aluminum Als are controlled in the smelting process; then, double-roller thin-strip continuous casting is carried out to cast strip steel with the thickness of 1.5-3 mm, and the strip steel directly enters a lower closed chamber with a non-oxidizing atmosphere after being discharged out of crystallization rollers and enters an online rolling mill under the closed condition to be subjected to hot rolling; and the rolled strip steel is cooled by adopting a gas atomization cooling mode,and the gas atomization cooling mode can effectively reduce the thickness of surface scale of the strip steel, improve the temperature uniformity of the strip steel and improve the surface quality ofthe strip steel. A finally produced steel coil can be directly used as a hot-rolled riffled plate / strip, can also be used as a finished riffled plate / strip after being trimmed and leveled, and can bewidely applied to the fields of buildings, machine manufacturing, automobiles, bridges, traffic, shipbuilding and the like.

Description

technical field [0001] The invention belongs to continuous casting technology and products in the metallurgical industry, and in particular relates to a thin patterned steel plate / strip and a manufacturing method thereof. Background technique [0002] Most of the traditional thin strip steel is produced by multi-pass continuous rolling of the slab with a thickness of 70-200mm. The traditional hot rolling process is: continuous casting + slab reheating and heat preservation + rough rolling + finishing rolling + cooling + Coiling, that is, firstly obtain a cast slab with a thickness of about 200mm through continuous casting, reheat the cast slab and keep it warm, then perform rough rolling and finish rolling to obtain a steel strip with a thickness generally greater than 2mm, and finally process the steel strip Laminar cooling and coiling complete the whole hot rolling production process. If it is necessary to produce a steel strip with a thickness of less than 1.5mm (inclusi...

AI Technical Summary

Problems solved by technology

At the same time, the contact of high-temperature strip steel with cooling water will cause many problems: first, water spots (rust spots) will be formed on the surface of the strip steel, which will affect the surface quality; second, the cooling water used for laminar flow cooling or spray cooling It is easy to cause uneven local cooling on the surface of the strip, resulting in uneven microstructure inside the strip, resulting in uneven properties of the strip and affecting product quality; third, uneven local cooling on the surface of the strip will cause deterioration of the shape of the strip , affecting the shape quality

[0009] However, due to the rapid solidification process characteristics of thin strip continuous casting, the produced steel generally has the problems of uneven structure, low elongation, high yield ratio, and poor formability; The grains have obvious inhomogeneity, which will lead to the inhomogeneous structure of the final product obtained after austenite transformation, resulting in unstable performance of the product

Therefore, it is difficult and challenging to use a thin strip continuous casting production line to produce high-strength thin-spec pattern plates. It is impossible to copy the traditional composition process, and breakthroughs in composition and process are required.

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