32results about How to "Reduce scale thickness" patented technology

A method for thin strip continuous casting to produce high-strength and high-corrosion-resistant steel, which includes the following steps: a) smelting, smelting according to the following chemical composition, and its chemical composition weight percentage is: C 0.02-0.06%, Si 0.1-0.5%, Mn 0.4‑1.7%, P≤0.02%, Cr 4.0‑6.0%, Ni 1.0‑3.0%, S≤0.007%, N: 0.004‑0.010%, Als<0.001%, total oxygen [O] T : 0.007‑0.020%, remaining Fe and unavoidable impurities, and, at the same time, satisfying: one or two elements in Nb: 0.01‑0.08% or V: 0.01‑0.08%; Mn / S>250; b) even Casting, double-roll thin strip continuous casting to obtain the cast strip; c) lower airtight protection, the cast belt directly enters the lower airtight chamber after leaving the crystallization roller, and the lower airtight chamber passes non-oxidizing gas; d) online hot rolling, the cast belt is sealed in the lower airtight chamber The room is sent to the rolling mill through pinch rollers, and rolled into strip steel; e) the strip steel is cooled by gas atomization cooling; f) the strip steel is coiled.

The invention discloses high-strength, thin-gauge and high-corrosion-resistance steel and a manufacturing method thereof. The high-strength, thin-gauge and high-corrosion-resistance steel comprises, by weight, 0.02-0.06% of C, 0.1-0.5% of Si, 0.4-1.7% of Mn, less than or equal to 0.02% of P, 4.0-6.0% of Cr, 1.0-3.0% of Ni, less than or equal to 0.007% of S, 0.004-0.010% of N, less than 0.001% of Als, 0.001-0.006% of B, 0.007-0.020% of total oxygen [O]T and the balance Fe and inevitable impurities, meanwhile, the high-strength, thin-gauge and high-corrosion-resistance steel contains one or twoof 0.01-0.08% of Nb and 0.01-0.08% of V, and the Mn / S ratio is greater than 250. According to the manufacturing method, the microalloy elements such as Nb / V and the B element are selectively added into steel, and 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 adopted for casting a cast strip, and the cast strip enters an online rolling mill under the closed condition to be subjected to hot rolling; and after rolling, a gas atomization cooling mode is adopted for cooling the strip steel.

A method for producing martensitic steel strip by twin-roll thin strip continuous casting, using scrap steel as raw material, making full use of residual Sn, Cu and other elements in scrap steel to smelt molten steel, and selectively adding Nb / Mo etc. Microalloying elements; during the smelting process, by controlling the basicity of slag, the type and melting point of inclusions in steel, the content of free oxygen in molten steel, and the content of acid-soluble aluminum Als; Strip steel, after the strip steel comes out of the crystallization roll, directly enters a lower airtight chamber with a non-oxidizing atmosphere, and enters the on-line rolling mill for hot rolling under airtight conditions; after rolling, the strip steel is quickly cooled by gas atomization Cool to below 300°C, and finally coil to obtain steel coils; it can also be subjected to isothermal tempering treatment, or entered into the continuous annealing production line for aging treatment.