Method for preparing high silicon thin steel strip through single-roller melt spinning method

Abstract

The invention discloses a method for preparing a high silicon thin steel strip through a single-roller melt spinning method. The method comprises the steps of 1) feeding high silicon steel mother alloy into a vacuum furnace for vacuum melting, and preheating a heat preservation ladle; 2) introducing a protective gas into the vacuum furnace and the heat preservation ladle till positive pressure is reached, opening a gate valve when the air pressure inside the vacuum furnace approaches the air pressure inside the heat preservation ladle, lowering the whole heat preservation ladle to a working position above a crystallization roller, turning on the crystallization roller, and releasing a puddle protective gas; 3) pouring molten silicon steel obtained through smelting into a spray ladle inside the heat preservation ladle, and turning on a gas stripping device, so as to enable molten steel to flow from a nozzle slot at the bottom of the spray ladle to the rotating crystallization roller below a nozzle to be quenched to form the thin strip; and 4) after the molten steel is poured completely, closing the gate valve, increasing the pressure of the protective gas inside the heat preservation ladle, and controlling the molten steel inside the spray ladle to be quickly and uniformly sprayed from the nozzle to the crystallization roller through a pressure closed-loop control till the strip spraying is over. The method has the advantages that the forming property of strip spraying is good, the strip width range is large, and a finished product is good in shape and magnetism.

Description

technical field [0001] The invention relates to a method for producing a silicon steel sheet, in particular to a method for preparing a high-silicon steel thin strip by a single-roll stripping method. Background technique [0002] Studies have shown that silicon steel with a silicon content (mass content, the same below) of 6% to 8% has the most excellent soft magnetic properties. This is because the development of ferrite is promoted with the increase of silicon in the alloy, so the steel's The initial magnetic permeability and maximum magnetic permeability are also gradually enhanced, and peak at 6% to 8%, which greatly reduces the hysteresis loss; when the silicon content is 7% to 12%, the resistivity of silicon steel also reaches the maximum value, which is the same as that of silicon steel. The amorphous alloy is equivalent, which minimizes eddy current loss; the increase in silicon content also reduces the magnetostriction of silicon steel, and drops to zero at 6.5%. ...

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Problems solved by technology

[0020] Among the manufacturing methods introduced above, the rolling method uses rolling, annealing, rolling, annealing, etc. repeatedly, resulting in a long processing cycle, low yield, high energy consumption, and magnetic properties that cannot reach the optimum range.

There are also researchers who add Cu, Cr, P, B and other trace elements to Fe-6.5% (mass) Si molten steel. Although some plasticity and workability can be improved, the final product has poor magnetic properties.

[0021] The CVD process has been successful, but there are still the following problems: 1) high deposition temperature, high energy consumption, severe equipment corrosion, and shortened life; 2) CVD process relies on SiCl 4 Formation of Fe by corroding the iron surface 3 Si is deposited, so corrosion pits and unevenness will occur on the surface, which requires warm rolling and leveling, which brings inconvenience to production; 3) FeC1 produced by CVD process 2 Exhaust gas not only seriously pollutes the environment, but also causes the loss of iron

[0022] At present, for the rapid solidification technology, the high-silicon steel thin strip produced by the single-roll stripping method is narrow in width and poor in shape; the thin strip casting and rolling process is still in the experimental stage, the efficiency is low, and there is still a gap from industrialization; the spray forming method High requirements on process equipment, few applications

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