How is stainless steel made? There are some differences in the manufacturing process between stainless steel and other carbon steels produced by Pandapipe. Stainless steel, as a disruptive alloy, has shown its indispensable value in many industries. Highly regarded for its excellent corrosion resistance, visual beauty and physical strength, it is widely used in a variety of industries such as construction, medical equipment and dining equipment.
Stainless steel is specifically produced by what method? How is stainless steel made? Let’s explore it together.
What Is Stainless Steel Pipe?
Composition of Stainless Steel- Stainless Steel Made Of
“Stainless steel” is actually a general term for various grades of steel, mainly made from iron and carbon through a two-step process. What distinguishes stainless steel is the addition of other alloying elements such as chromium (Cr) and nickel (Ni) to create corrosion-resistant products.
According to the standard definition of GB/T20878-2007, the main characteristics of stainless steel are rust and corrosion resistance, and its chromium content should not be less than 10.5%, while the carbon content should not exceed 1.2%.
How Is Stainless Steel Made?
How is stainless steel made? The manufacture of stainless steel involves a series of processes.
Smelting
In order to produce stainless steel, raw materials such as iron ore, chromium, silicon and nickel need to be melted and mixed in an electric furnace. This process often requires high temperature treatment for up to 8 to 12 hours. The molten mixture is then poured into the mold to form products of different shapes, such as generous billets, billets and slabs.
Decarbonization
The molten material is decarburized in a vacuum oxygen decarburization (VOD) or argon oxygen decarburization (AOD) system. Depending on how much carbon is removed, this process can produce a standard alloy or a low-carbon version of the product – for example, the difference between 304 and 304L stainless steel. This treatment has a significant effect on the tensile strength and hardness characteristics of the final product.
Hot Rolling
When the slab arrives at the hot mill, it is transferred to another furnace, and the hot material is then sent to the roughing mill. In the process of roughing mill operation, the thickness of the equipment is reduced by rolling back and forth. As the thickness of the slab decreases, it will gradually become a slender shape and eventually be rolled up.
By using additional rolling mills, long strips or strips can further reduce their thickness.
Pickling
The annealing process often creates oxide or deposits on the surface of the steel, which need to be removed by a specific process. Pickling is a common and effective method. This method usually uses a nitric hydrofluoric acid bath to treat the steel, thus effectively removing scale. Another electric cleaning technology uses a cathode and phosphoric acid to apply an electric current to the steel surface to remove scale.
Cold Rolling
Choose cold rolling technology for finer scales or better surface brightness. It occurs below the recrystallization temperature of steel. The cold rolling process utilizes small diameter wheels and a series of support wheels to produce smooth, wide stainless steel plates to meet tight tolerances.
Cutting
Stainless steel can be cut with a round knife, sawing with a high-speed blade, or blanking with a punch. In certain cases, alternative methods such as flame cutting, plasma cutting and water jet cutting can also be used.
Surface Treatment
In the manufacturing and processing of stainless steel, it is also necessary to meet the mechanical properties standards specified by American Society for Materials and Testing (ASTM) for key characteristics such as toughness and corrosion resistance. Metallography, as a discipline, is often combined with corrosion testing for quality control to ensure that product performance meets requirements.
Quality Control and Testing
In the manufacturing and processing of stainless steel, process control is important, but it is also important to comply with the mechanical properties standards specified by the ASTM, especially for key characteristics such as toughness and corrosion resistance. Metallography, as a discipline, is often combined with corrosion testing for quality control to ensure that product performance meets requirements.
Application of Stainless Steel
How is stainless steel made? Look at the following formula:
Stainless steel = Iron + Chromium (>10.5%) + some other material
The equations mentioned above provide the basis for stainless steel alloys, but all the elements are used to make different grades of stainless steel. These different grades of alloys are commonly used to make materials used in industries such as automobiles, construction and industrial equipment.
These different levels have their own unique properties and roles, and are therefore used for a variety of purposes in many situations. Although the production of stainless steel is mainly concentrated on 10 alloys, the types of stainless steel alloys that can be produced now exceed 250.
How Is Stainless Steel Made Conclusion
In summary, every production link of stainless steel must be strictly regulated to ensure that products have high quality and excellent performance.
With the continuous development of science and technology and the growth of the market, the manufacturing technology of stainless steel will continue to innovate and improve, provide convenience.
