Steelmaking deoxidizer and preparation method, application and use method thereof

Abstract

The invention discloses a steelmaking deoxidizer. The steelmaking deoxidizer comprises the following raw materials of, by weight, 35%-45% of silicon, 4%-6% of strontium and the balance iron. A preparation method of the steelmaking deoxidizer comprises the following steps of (1), weighing quartz stone, celestite and iron filings by weight; and (2), feeding the iron filings, the quartz stone and thecelestite in sequence, heating to completely melt, cooling, discharging and crushing to obtain the steelmaking deoxidizer. A use method of the steelmaking deoxidizer comprises the steps of (1), smelting molten steel to 1500-1700 DEG C, and standing at constant temperature for 3-5 minutes; (2), adding a deslagging agent to remove scums, and then adding the steelmaking deoxidizer to stand for 3-5 minutes; and (3), adding the deslagging agent again to remove the scums. The steelmaking deoxidizer is thorough in deoxidation, carbides can be formed into equiaxed crystals by simple one-time precipitation deoxidation, inclusions are spheroidized, and crystal grains of steel are refined, so that the thermal fatigue performance of a material is greatly improved, meanwhile, the smoke dust is less, and thus the steelmaking deoxidizer is environmentally friendly.

Description

technical field [0001] The invention relates to the technical field of metal smelting, and more specifically relates to a steelmaking deoxidizer and its preparation method, application and use method. Background technique [0002] According to the development of the automobile industry in recent years and the improvement of energy-saving and environmental protection requirements, automobile engines also require replacement. The transition from gray cast iron to current heat-resistant steel. The key link in heat-resistant steel smelting is deoxidation and metamorphism technology. During the smelting process, effective deoxidation is required. During the refining process, carbides must be transformed from columnar crystals to equiaxed crystals. Among them, how to make inclusions form spherical inclusions is the current problem to be solved. main problem. [0003] The traditional heat-resistant steel smelting process uses alloys such as rare earth barium, calcium, magnesium, ...

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Problems solved by technology

[0003] The traditional heat-resistant steel smelting process uses alloys such as rare earth barium, calcium, magnesium, and aluminum for deoxidation. The disadvantages are as follows: ① Due to the low evaporation point of calcium, after adding it on site, a large amount of calcium evaporates to form smog, which not only pollutes the environment, but also reduces the visibility on site. Production safety accidents are prone to occur; ②Metal aluminum and magnesium are expensive, and the cost of steelmaking is high. At the same time, aluminum is easy to form alumina inclusions in the steel, which affects the performance of the steel. Magnesium is a strong supercooling element, and the molten steel is easy to supercool after adding. Columnar crystals lead to concentration of casting stress and decrease in fatigue performance after service; ③ This deoxidation method cannot effectively solve the problems of complete deoxidation and spheroidization of inclusions

[0004] At present, silicon-aluminum-barium-iron deoxidizers are widely used, which contain 22%-30% of silicon, 30%-40% of aluminum, 3-12% of barium, and the balance is iron. Although the alloy prepared by using this deoxidizer overcomes the Deoxidation of calcium silicon, pure aluminum and magnesium has the disadvantages of reducing the total amount of non-metallic inclusions, improving the size and distribution of inclusions, and saving aluminum, but the effect of refining steel grains is poor, and due to the There is a large amount of residual aluminum in the liquid, and the casting is easy to form porosity defects

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