Cast steel can be divided into two categories:cast carbon steel and cast alloy steel

www.welongcast...
Contact Us: [e-mail]
Cast steel is much higher in terms of strength and toughness than ordinary cast iron, and is often used in working conditions that withstand heavy loads and impacts. Cast steel has weldability, which is not only conducive to the repair of defects, but also can use the method of casting and welding to cast some heavy and complex castings in sections and then weld them into a whole. Compared to forged steel, cast steel can be used to produce parts or blanks with very complex structures. However, the melting point of cast steel is high, the casting performance is poor, the production process and smelting equipment are complex, and the requirements for raw materials are high. Despite this, cast steel is still an excellent structural material and is widely used in industry.
Cast steel can be divided into two categories: cast carbon steel and cast alloy steel according to its chemical composition.
In order to improve and enhance certain properties of cast carbon steel, one or more alloying elements are added to the cast steel, which is called casting alloy steel. The most commonly used alloying elements in casting steel are chromium, molybdenum, nickel, tungsten, cobalt, aluminum, vanadium, titanium, and boron. When manganese content exceeds 0.8% and silicon content exceeds 0.4%, it is also considered casting alloy steel. Casting alloy steel can be divided into low-alloy steel, medium-alloy steel, and high-alloy steel according to the content of alloying elements.
The steelmaking equipment used in the steel casting workshop includes electric arc furnace, ladle refining furnace, open-hearth furnace, induction electric furnace and plasma electric arc furnace. Induction furnaces and plasma electric arc furnaces are mainly used to smelt high-grade alloy steels and high-temperature alloys, and are used to pour castings with high requirements and complexity. Electric arc furnace is the most widely used in steel casting workshop, it has fast melting speed, high temperature of molten steel, and easy to control, has good dephosphorization and desulfurization conditions, can smelt carbon steel and alloy steel with high quality, and is suitable for pouring various types of castings.
The materials used in steelmaking are mainly refractories, metal charges and other auxiliary materials.
The metal materials used in EAF steelmaking include scrap steel, pig iron, scrap iron, ferroalloys and deoxidizers.
After the loading is completed, the furnace lid is covered, and the electricity can be melted after checking that it is correct. The melting process of the charge is that the charge under the electrode is melted first, forming three melting wells, and then the electrode continues to move downward, and the charge continues to melt, reaching the lowest position after 15~25min, forming three small wells, that is, the so-called "piercing well". As the melting progresses, the molten steel level at the bottom of the furnace rises, and the electrode should rise upwards accordingly.
As a result, the charge around the electrode collapses, the so-called "collapse". In this way, the charge is melted gradually. To speed up the melting process, a rake can be used to manually push the charge farther away from the electrode and less likely to be melted underneath the electrode, an operation called "pusher melting". After there is a certain amount of molten steel in the furnace, the method of "oxygen blowing and melting" can also be adopted to accelerate the melting of the charge. The oxygen blowing pressure is generally controlled at about 0.5MPa.
The oxygen blowing tube is inserted into the molten steel from the furnace door to blow oxygen, but not deep into the bottom of the furnace or close to the furnace wall to prevent damage to the furnace lining.
During the melting process, the slag should be made. The purpose is to cover the molten steel, avoid direct exposure of the molten steel to the arc and inhalation and oxidation, and to remove a part of the phosphorus during the melting period, while stabilizing the arc.
#casting #sandcasting