The types of stainless steel production process and the advantages and disadvantages of stainless steel manufacturing include a series of processes. First, the steel is melted and then cast into a solid form.
After various forming steps, the steel is heat treated, then cleaned and polished to achieve the desired surface. It is then packaged and sent to a fabricator who welds and joins the steel to produce the desired shape.
Melting and casting: In an electric furnace, first the main components are melted collectively. This step usually requires 8 to 12 hours of high temperature.
After melting, the molten steel is poured into semi-finished form. These include blooms (rectangular), billets (round or square, 1.5 inches or 3.8 cm thick), slabs, bars, and tubes.
Forming: 2 Next, the semi-finished steel goes through the forming process, first hot rolling, where the steel is heated and passed through large rolls.
Blooms and billets are made into rods and wires, while slabs are made into plates, strips, and sheets. Bars are available in all grades in 0.25″ (0.63 cm) round, square, octagonal, or hexagonal.
The diameter or size of the wire is usually up to 0.5 inches (1.27 cm). The board is over 0.1875 inches (0.47 cm) thick and over 10 inches (25.4 cm) wide. The tape is less than 0.185 inches (0.47 cm) thick and 24 inches (61 cm) wide. The thickness of the sheet is less than 0.1875 (0.47 cm) and its width is more than 24 (61 cm).
Hyperthermia: 3. After forming stainless steel, most types must undergo an annealing step. Annealing is a heat treatment in which steel is heated and cooled under controlled conditions to reduce internal stress and soften the metal. For greater strength, some steels are heat treated.
However, this heat treatment – also known as age hardening – must be carefully controlled, as even small changes in recommended cooling temperature, time or speed can seriously affect performance.
Lower aging temperatures result in higher strength and lower fracture toughness, while aging at higher temperatures results in lower strength and harder materials.
While the rate of heating to the aging temperature (900 to 1000°F or 482 to 537°C) does not affect performance, the rate of cooling does.
Post-aging treatment (quick quench) can increase strength without significant reduction. One such process involves quenching the material in an ice water bath at 35°F (1.6°C) for at least two hours. The type of steel determines the type of heat treatment.
In other words, it is austenite, ferrite or martensite. Austenitic steels are heated above 1900°F (1037°C) for a period depending on the thickness.
Water quenching is used for thick sections, while air or air blast quenching is used for thin sections. If cooling is too slow, carbide precipitation may occur.
This accumulation can be removed by thermal stabilization. In this method, the steel is held at a temperature of 1500 to 1600 degrees Fahrenheit (815 to 871 degrees Celsius) for several hours.
Sometimes, to achieve proper heat treatment, it is necessary to clean the surface of some pollutants before heat treatment. The type of steel determines the heat treatment method.
In other words, austenite, ferrite or martensite. Austenitic steels are heated above 1900°F (1037°C) for a period depending on the thickness.
Water quenching is used for thick sections, while air or air blast quenching is used for thin sections. If cooling is too slow, carbide precipitation may occur.
This accumulation can be removed by thermal stabilization. In this method, the steel is held at a temperature of 1500 to 1600 degrees Fahrenheit (815 to 871 degrees Celsius) for several hours.
Sometimes it is necessary to bend the surface of the contaminant before the heat treatment in order to obtain the proper heat treatment.
Descaling 4 Annealing causes scale or deposits to form on the steel. Limescale can be removed using different methods. Pickling, one of the most common methods, uses a nitric-hydrofluoric acid bath to descale the steel.
In another method, electrocleaning, an electric current is applied to the surface using a cathode and phosphoric acid, and deposits are removed.
The annealing and descaling steps are done in different steps depending on the type of steel being processed. For example, after initial hot rolling, bars and rods go through further forming steps (hot rolling, further forging or extrusion) before annealing and descaling.
On the other hand, sheet and strip are subjected to the initial annealing and descaling stage immediately after hot rolling.
After cold rolling (passing the rolls at relatively low temperatures), the thickness is further reduced and the sheet and strip are re-annealed and descaled. The final stage of cold rolling then prepares the steel for final processing.
Cutting: 5 Cutting operations are often necessary to obtain the desired blank shape or size for cutting the part to final size.
There are many methods for mechanical cutting, including direct cutting with guillotine knives, circular cutting with horizontal and vertical circular knives, sawing with high-speed steel blades, cutting and tilting. Blanking uses metal punches and dies to cut shapes.
Nibbling is the process of creating a cut by drilling a series of overlapping holes, suitable for irregular shapes.
Finishing
6 Surface finish is an important feature of stainless steel products and is particularly important in applications where appearance is important. Certain surface treatments also make stainless steel easier to clean, which is obviously important for sanitary applications.
Better corrosion resistance is also provided by the smooth surface produced by polishing. On the other hand, lubrication applications often require rough machining to facilitate further manufacturing steps.
Surface finish is the result of processes used to make different shapes or the result of further processing. There are several ways to complete it.
A matte surface is produced by hot rolling, annealing and descaling. Hot rolling is followed by cold rolling on polished rolls to create a stunning finish.
Highly reflective gloss coatings can be produced by cold rolling combined with annealing in a controlled atmosphere furnace, abrasive grinding, or finely ground surface finishing.
A mirror finish is created by polishing with finer abrasives followed by heavy polishing. A grinding wheel or belt is usually used for grinding or polishing.
Stainless Steel Advantages and Disadvantages
Advantages of stainless steel
Corrosion resistance stainless steel is an alloy that contains at least 10.5% chromium and enough nickel (or manganese) to leave at least 4% chromium in the stainless steel section. This compound has a very good resistance to corrosion and for this reason it is used in kitchen sinks, building construction and many other places.
The excellent mechanical properties of stainless steel make it a strong and durable metal that can be used for many purposes.
The high tensile strength of stainless steel makes it ideal for home construction equipment such as door frames, sinks, and other structures. Stainless steel is also an excellent material for making other products such as cookware and household appliances because it is resistant to corrosion.
Stainless steel is also commonly used in household appliances due to the high strength of the metal.
