Stainless steel can be fabricated using all traditional forming methods. Austenitic stainless steel can be rolled, spun, deep drawn, cold forged, hot forged, or stamped using force and tension. Although stainless steel is very strong and has a high hardening rate, it is very ductile, allowing it to be cold formed.
Deciding on the type of stainless steel for a project requires understanding the many types, which are divided into four families - austenitic, ferritic, martensitic and duplex.
The largest of the four groups is austenitic, made from a combination of steel, nickel or manganese, and nitrogen. It is the main choice for producing a wide variety of products.
Ferritic stainless steel contains carbon steel and chromium. Martensitic stainless steel comes in four grades with a combination of iron, chromium and carbon. How the materials are combined and depending on the addition of other alloys determines the type of martensitic stainless steel.
Duplex stainless steel is a combination of austenite and ferrite in various percentages and proportions.
Types of stainless steel are numbered. The type of numbering system depends on who does the classification, as they differ between Great Britain, the International Organization for Standardization, Japan, Europe, Germany and China. Regardless of the classification system, each organization has the same basic requirements and standards that define what stainless steel is.
The manufacturing method for forming stainless steel depends on the grade and type of alloys. Each grade has different qualities that make it easier or harder to form. They all have in common that they are corrosion resistant and durable, although some grades are not as good.
Types of stainless steel for manufacturing
Different types and grades of stainless steel have different applications. When choosing stainless steel, careful consideration should be given to the use of the product, the method of forming, and equipment to be used. Misjudging any of these factors can lead to an unfortunate outcome.
There are five basic types of stainless steel that manufacturers use to make industrial and household products. What should be kept in mind is the different grades of stainless steel beyond these five types.
Ferritic stainless steel has a chromium base with a low amount of carbon. It is not ideal for conditions that require welding, but its high corrosion resistance makes it perfect for marine environments.
Austenitic stainless steel is the most commonly used. It can be welded, formed and modified for various purposes. Austenitic stainless steel is formed by combining nickel, manganese and nitrogen. The austenitic form of stainless steel can be cold worked, improving its hardness, strength and stress resistance. It can also be heated to form, but returns to its original strength after cooling. Austenitic stainless steel is classified into the 200 and 300 series of stainless steels.
Duplex stainless steel has a combination of the properties of austenitic and ferritic and offers the advantages of both, from which it gets its name by using 50% of each alloy. It has twice the strength of other stainless steels and can withstand extreme pressure. The low cost of duplex stainless steel makes it attractive, although it is the least used of the varieties of stainless steel.
Martensitic stainless steel is a composition of iron, chromium and carbon, a 410 type of stainless steel. It has high strength, hardness and wear resistance, but has poor weldability and low plasticity. Martensitic stainless steel is used for cutting tools and dental and surgical instruments.
Precipitation hardening (PH) stainless steel is corrosion resistant and can be heated to achieve tensile strengths of 850MPa and higher, up to four times harder than austenitic stainless steel. It is an alloy produced by combining copper, molybdenum, aluminum and titanium. There are three types of PH stainless steel - low carbon martensitic, semi-austenitic, and austenitic.
Applications of stainless steel
The applications of stainless steel vary widely due to the metal's versatility, relatively low cost, ease of fabrication, aesthetic appeal and recyclability. Although you wouldn't know it, stainless steel has a huge impact on everyday life and is used in a wide variety of industries. The list of applications for stainless steel is almost limitless, some of the main application areas are..
Because stainless steel is resistant to corrosion and easy to maintain, it is widely used in both domestic and commercial catering environments. In your kitchen at home, you may find stainless steel used to make your sink, your oven, cutlery or canopy, while commercially, it is also used as countertops, splashbacks and kettles. Different grades of stainless steel are used for different applications depending on their need for corrosion resistance.
Because of its wear resistance and aesthetic appeal, stainless steel is often used as street furniture, posts and railings or signage.
In public restrooms, the need for a hard-wearing, corrosion-resistant material is crucial. Since different grades of stainless steel have different cost and corrosion properties, this metal is well suited for making products such as hand dryers, soap dispensers and toilet roll holders.
Although aluminum and steel play a major role in the automotive industry, stainless steel still makes up a large percentage of the metal used. It is used on many vehicles in exhaust systems and sill plates and more specifically in the manufacture of tanker trucks and refuse and recycling vehicles.
Because it is relatively easy to weld, has good structural properties and requires little maintenance, pressure vessels are usually manufactured from stainless steel, and with the added benefit of corrosion resistance, it is also widely used in the food and brewing industries.
Most power plants require corrosion-resistant and durable metals. Because of its corrosion-resistant properties, stainless steel is widely used in various types of power plants.
In the nuclear power industry, stainless steel, especially with low cobalt content, is often used for radiation containment and power generation.
Turbines in gas, steam and water power plants are also made of stainless steel. It is preferred in these applications because of its corrosion and heat resistance.
Pulp and paper industries
Pulp and paper industries prefer to use stainless steel in their applications to avoid iron contamination of their products and also to prevent corrosion of the equipment.
Chemical, oil and gas processing industries
From stainless steel tanks, pipes, valves and tanks, stainless steel is an important component in what is considered one of the most stainless steel industries.
Stainless steel tankers can be seen up and down the highways carrying a variety of products.
Stainless steel, in its many forms, has become a necessary part of manufacturing products. Since its introduction more than a hundred years ago, producers and manufacturers have come to rely on its indestructible qualities to manufacture many of the objects we depend on. Although other metals have been developed in the past thirty years, it is very likely that more forms of stainless steel will come in the future.